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Electrical Gurus Needed - Wierd Ignition Issue!!

Posted By: cjskotni

Electrical Gurus Needed - Wierd Ignition Issue!! - 10/25/12 10:13 PM

Guys,

I have been grappeling with a strange, elusive issue now for the past 6 weeks and it's got me about to torch my Charger to the ground!

Car is a 1973 Charger. Everything on the electrical system is stock except for a 100 amp alternator (3 wire) and dual electric fans. Ignition is factory electronic ignition and MP distributor. Engine bay wire harnesses are all NEW repro.

I had this car dyno'ed back in August and tuned and it had run fine for about 25-50 miles worth of driving. Started great, good power, never died...

Problem "began" when I was driving the car and it simply cutoff while I was crusing. Just lost power and died. This was the first time I had run with hadlights so I figured this must be a low voltage situation. I went ahead and upgraded the alt to a 100 amp unit. Problem still existed.

I then replaced or swapped the following to see what the issue was:

- ECU box (tried two new ones)
- VR
- coil
- ballast resistor
- cap/rotor
- dist pickup

Replacing all these parts has done NOTHING to fix this issue. Double checked and all grounds are great. I can crank the car (bit of a harder start now) but it runs fine for about 10-15 minutes and then just idles down and dies. Doesn't misfire or pop...just dies. It cannot be restarted until it is cooled off.

I have monitored battery voltage and even disconnected the cooling fans and the charging circuit is not the cuplrit here. After the car dies, it still has plenty o' juice to crank (or try). Heck it will even die when the battery is charging at 13+ V.

After getting the engine to die, I pulled the #7 plug wire and hooked to spark plug tester. Seems to be erratic/no spark when this problem arises which would make sense. We have a running motor that just dies....no spark, right?

So afer replacing/swapping all these parts, problem is still there! What gives?

What else could cause this? Just about the entire ignition system has been replaced. Is there a underdash wire that could be shorting or something? I am assuming this must be heat-related as we run OK until it dies....

The funny thing is, this problem just came out of the blue. I had not changed ANYTHING ANYWHERE to begin this cycle...

I am running out of ideas here and wasting a lot of time in the garage.

Much more time on working this issue in the garage and my wife is going to serve me divorce papers!

Any help or ideas here are appreciated. What else could stop a running motor and kill its spark? Please !
Posted By: Andrewh

Re: Electrical Gurus Needed - Wierd Ignition Issue!! - 10/25/12 10:34 PM

well eliminate some of the wiring.
run a hot directly to the VR sensing line.
it should back feed the ecu, balast resister/coil.

see if it will continue to run.

the next step would be if it still dies, to start swapping old parts back in during the won't start period until it does.
Posted By: John_Kunkel

Re: Electrical Gurus Needed - Wierd Ignition Issue!! - 10/25/12 10:46 PM


Check/clean the firewall bulkhead disconnect terminals.
Posted By: cjskotni

Re: Electrical Gurus Needed - Wierd Ignition Issue!! - 10/25/12 11:04 PM

Quote:

well eliminate some of the wiring.
run a hot directly to the VR sensing line.
it should back feed the ecu, balast resister/coil.

see if it will continue to run.

the next step would be if it still dies, to start swapping old parts back in during the won't start period until it does.



Is this the blue wire? Just jumper from + on battery to this?


Quote:

Check/clean the firewall bulkhead disconnect terminals.



These pare pretty darn clean as the engine bay harness is new. The underdash harness is old though so that's why I was wondering if that could be an issue. I have a new dash harness I have yet to put in but I'd like to clear this up before I install that.
Posted By: 71_deputy

Re: Electrical Gurus Needed - Wierd Ignition Issue!! - 10/26/12 12:14 AM

ALSO check the plugin harness from the ing.switch to the main harness for burnt/melted/corroded connections!!
Posted By: RapidRobert

Re: Electrical Gurus Needed - Wierd Ignition Issue!! - 10/26/12 02:37 AM

I'd hook a timing light to the coil wire & double check that it ain't firing then I would make up some jumper wires and jump 12V to the upstream side of the ballast then from the downstream side of the ballast to the coil positive primary terminal and jump 12V to the hot input wire at the ECU pentastar connector and seperate the pickup connector and jump from it (2 wires) to the ECU pentastar connector. Then jump directly from the coil negative primary terminal to the black/yellow wire pigtail on the ECU pentastar connector. I would strip the (4) wires at the ECU pentastar connnector several inches out from the connector base on the pigtails to make SURE there's a Direct Connnection to confirm/deny that it's a wiring problem. EDIT If you dont want to do any unsightly T ing into the pentastar harness you could unplug it & use some female butt connectors to connect your jumpers to the ECU pins if you choose to do this
Posted By: hooziewhatsit

Re: Electrical Gurus Needed - Wierd Ignition Issue!! - 10/26/12 02:37 AM

Quote:

ALSO check the plugin harness from the ing.switch to the main harness for burnt/melted/corroded connections!!



This, and/or check to make sure you're still getting power through the ignition switch itself, both before and after the problem, so you know what voltages should be where.
Posted By: TheBlueBeast

Re: Electrical Gurus Needed - Wierd Ignition Issue!! - 10/27/12 01:38 AM

I will go out on a limb here. I have previously stopped giving advice via the internet since someone got mad when I diagnosed his problem as being a timing chain despite his assurances that it was perfect. Turned out it was the problem.
Now back to your problem.
Run a ground wire from any place to the mounting bolts of the ECU. The ECUs MUST be grounded to properly function and will give you all kinds of insanity to figure it out. I always go from the hood hinge bolt back to the mounting bracket where the ECU bolts to the bracket.
This may not fix the problem but it can't hurt.
One thing I learned from my grandfather (I wish I had listened more now) was that, "You electrical connection is only as good as your ground." Good Luck.
Kevin
Posted By: dvw

Re: Electrical Gurus Needed - Wierd Ignition Issue!! - 10/27/12 02:52 PM

Did you go over the circuits with a headlamp load tester as a was suggested in the earlier post? The grounds as well. You've all ready changed al the components. Wiring must be verified next. I fix prototype vehicles with brand new harnesses every day. Can't tell you how many corroded, loose crimps, grounds cause off the wall stuff. It's not rocket science, just good detective work. You'll find it. Just go step by step.
Doug
Posted By: cjskotni

Re: Electrical Gurus Needed - UPDATE - 11/11/12 09:22 PM

Guys,

I appreciate the suggestions. I have checked grounds, run dedicated ground jumpers to the VR and ECU box housing. I have tried jumping from the starter relay to the blue ignition circuit after the motor dies. I cannot figure this out!

Since my last post I have done the following:

- went ahead and put in the brand new dash harness and fuse block. All connections cleaned and packed with dielectric grease

- gauge cluster is out of car and the two ammeter leads are just tied together and taped over

- rebuilt steering column and put in new ignition switch

After doing all this - no change! The motor starts just fine from cold and will run 15 minutes or so and then you see it start idling lower and lower for about a minute and then it dies! No surging/missing/popping...just dies. After this, can't restart until cooled off again.

When dead, checked voltage on coil in "run" it gets ~3V and "start" gets ~7.5V. I hooked up a spark plug tester and I am getting spark at the plugs so coil is firing.

I am at my wit's end here! I have replaced just about everything on the ignition circuit and can't shake this problem. I have jumpered grounds, swapped parts, and bypassed the hanress numerous times/ways! EVERY single wire on this car is new! We aren't even dealing with cruddy 40 yr old wires!

Where do I look now? Could this be a mechanical issue?? I can't see what could be wrong with the motor itself that would go from purring to dead in 15 mintutes everytime! Carb issue?? I am about 99% sure I'm getting fuel though....

I wouldn't mind taking this to a mechanic but I don't know of any that would know this old stuff and be any better at this than I am!

Any other ideas?
Posted By: stumpy

Re: Electrical Gurus Needed - UPDATE - 11/11/12 09:27 PM

Start should get 12v+ and run should be at around 9v.Find out why the low voltage and that will fix your problem. Start at the battery and trace the ignition all the way through.
Posted By: jlatessa

Re: Electrical Gurus Needed - UPDATE - 11/11/12 09:29 PM

I'm worried about that 1% fuel thing.
Slow fuel starvation maybe, like no vent or something???

Drives you crazy!!

Joe
Posted By: cjskotni

Re: Electrical Gurus Needed - UPDATE - 11/11/12 10:56 PM

I think we **may** be on to something here. I am not going to get my hopes up though....

So with the ley in "run" I have ~11.7V on the blue side of the ballast resistor and ~4V on the brown side. This is quite a drop. I measured resistance across the resistor and it shows ~2 ohms which should be OK....

I am guessing this means there must be a huge draw on this circuit somewhere that is causing such a drop on 2 ohms! This is with choke disconnected. The only other two things I have are the ignition wire for the fan relays, the ECU, and the blu field on the alternator. Must be one of the three shorting to ground or the wires themselves....

Also, I have ~1V on the "-" terminal of the coil in "run". Is this normal or supposed to be grounded (near 0 V)?
Posted By: 71_deputy

Re: Electrical Gurus Needed - UPDATE - 11/12/12 02:02 AM

I see that you have changed the coil- but was it a new one or old/borrowed one???

almost sounds like as it warms up it shorts out!!

my
Posted By: RapidRobert

Re: Electrical Gurus Needed - UPDATE - 11/12/12 03:30 AM

Quote:

I am getting spark at the plugs so coil is firing. Carb issue?? Any other ideas?

You wouldn't happen to have another carb you could sub in for a quick comparison would you? And on the current carb will it still give a healthy accell pump shot when it dies?
Posted By: cjskotni

Re: Electrical Gurus Needed - UPDATE - 11/12/12 03:34 AM

Quote:

I see that you have changed the coil- but was it a new one or old/borrowed one???

almost sounds like as it warms up it shorts out!!

my



Coil I swapped in was the stock replacement from Advance Auto, brand new.


Ok here is what I get when I go from run to start with the starter motor disabled (all volatges across + to - coil terminals):

With coil leads off the coil: ~10.6V run and ~11.5V start

With leads connected to coil: ~3V run and ~7.4V start (spikes @ 10.6V momentarily)

This leads (no pun intended) me to believe the coil is almost a large short (lower resistance than ballast) so it "takes" less of the voltage than the ballast...hence the voltage difference between the connected/unconnected leads.

Remembering back from how a generic coil should work, this makes sense, low current draw at first moments then goes to almost a short as time goes on...

Also the coil shows primary resistance of around 1.2 ohms and secondary of ~6.2 Kohms. It is an MSD Blaster II.

Is this normal? Can anybody tell me here what a "healthy" coil voltage should show in "run" position with leads connected? I pulled the harness apart and I am pretty sure the wires are fine from ballast to the coil. Wires look fine from coil back to ECU as well...

Pulling out what little hair I have left here!
Posted By: Swedcharger67

Re: Electrical Gurus Needed - UPDATE - 11/12/12 09:46 AM

I can't comment on blue and brown sides of things, but generally speaking:
- the 11.7V at the "high side" of the ballast resistor seems low. You should have full battery voltage here (i.e. about 13-14 volts engine running). The low voltage may indicate you have a bad connection in the feed to the ballast resistor (i.e. from the ignition switch/bulkhead connectors).
- Your measured resistance is 1.2 Ohms (coil, normal for a Blaster 2 if I remember correctly) and 2 Ohm (probably normal for a ballast resistor). This means you have a current which is U/(1.2+2). With 11.7V the current is 3.66 Amps.

This means that the voltage drop across the ballast resistor is 3.66A * 2 Ohms = 7.3 volts (if you measure to ground you have 11.7-7.3= 4.4 Volts on the positive terminal of the coil)

Now we come to the problem with measuring:
- On the "low side" of the ballast resistor you have a square wave type voltage, and the same on the low side of the coil (towards the ECU). With a normal universal multimeter you cannot get an accurate measurement, because these meters can only measure a DC voltage/current, and an AC sine wave voltage/current. But you have a square wave (not pure DC, not a sine wave AC), and all readings will be incorrect. They can however be used for indications, but not for any accurate calculations.
Hope this gives you some ideas how to compare with your measurements.

Basically your values seem correct, the low voltage to the ballast resistor would interest me.
You can always put a direct 12V feed to ballast resistor, and see if the engine keeps running.

The ignition coil will be a bit slow to start drawing current (because of the inductance, like to start spinning a wheel), but it increases rapidly and remains constant at Ucoil/Rcoil i.e. 4.4V/1.2Ohms = 3.6 Amps. The time usually allowed by electronics to charge an ignition coil is approx. 5/1000 seconds (5 milliseconds). An old points system is different with a variable time (longer for low rpms, shorter for high rpms...).

Sorry for the long text, early morning here and new energy...good luck in finding the bad connection.
Posted By: cjskotni

Re: Electrical Gurus Needed - UPDATE - 11/12/12 12:56 PM

Quote:

I can't comment on blue and brown sides of things, but generally speaking:
- the 11.7V at the "high side" of the ballast resistor seems low. You should have full battery voltage here (i.e. about 13-14 volts engine running). The low voltage may indicate you have a bad connection in the feed to the ballast resistor (i.e. from the ignition switch/bulkhead connectors).
- Your measured resistance is 1.2 Ohms (coil, normal for a Blaster 2 if I remember correctly) and 2 Ohm (probably normal for a ballast resistor). This means you have a current which is U/(1.2+2). With 11.7V the current is 3.66 Amps.

This means that the voltage drop across the ballast resistor is 3.66A * 2 Ohms = 7.3 volts (if you measure to ground you have 11.7-7.3= 4.4 Volts on the positive terminal of the coil)

Now we come to the problem with measuring:
- On the "low side" of the ballast resistor you have a square wave type voltage, and the same on the low side of the coil (towards the ECU). With a normal universal multimeter you cannot get an accurate measurement, because these meters can only measure a DC voltage/current, and an AC sine wave voltage/current. But you have a square wave (not pure DC, not a sine wave AC), and all readings will be incorrect. They can however be used for indications, but not for any accurate calculations.
Hope this gives you some ideas how to compare with your measurements.

Basically your values seem correct, the low voltage to the ballast resistor would interest me.
You can always put a direct 12V feed to ballast resistor, and see if the engine keeps running.

The ignition coil will be a bit slow to start drawing current (because of the inductance, like to start spinning a wheel), but it increases rapidly and remains constant at Ucoil/Rcoil i.e. 4.4V/1.2Ohms = 3.6 Amps. The time usually allowed by electronics to charge an ignition coil is approx. 5/1000 seconds (5 milliseconds). An old points system is different with a variable time (longer for low rpms, shorter for high rpms...).

Sorry for the long text, early morning here and new energy...good luck in finding the bad connection.



Thanks for the analysis so I don't feel quite so stupid now.

I should have noted that all these measurements are with the engine off. So the voltage loss through the bulkhead connectors/ignition switch is about 1 V compared to the battery + terminal.

Robert, what do you think could be wrong with the carb? I had this car tuned before this stuff happened and everything was fine (no dying issue). The guy went through the carb as well. I don't have another carb unfortunately but is there anything I should look for?
Posted By: moparmarks

Re: Electrical Gurus Needed - UPDATE - 11/12/12 01:12 PM

When the motor dies does the carb still have fuel? Still squirting out the nozzles?
Posted By: RapidRobert

Re: Electrical Gurus Needed - UPDATE - 11/12/12 03:10 PM

I'd let it idle in your driveway till it acts up then see if the AP still has a squirt & have the timing light ready to go & hooked up to the coil wire & immediately see if you have spark. Is the pickup gap good? I'd maybe take the top off of the carb & the idle mix screws out & blast it with a can of starting fluid but as said it sure sounds like a classic ign part acting up when hot. It's possible & does happen pretty regularly that one of the new ign parts you subbed in is bad tho it'd be out of the question to replace some or all of em again without knowing which one was bad. I'd start by using the timing light & if it confirms an ign prob then bypassing all of the harnesses with jumper wires to confirm/deny it's a wiring issue which I dont think it is then assuming it ain't the carb/vac leak/fuel starvation that only leaves the ign hard parts. Seperate the pickup pull apart connector & drag/tap the male end of the eng half of the conector across a ground & if the large coil wire (dist end) held 1/4" from ground now sparks (key on) then that points to the pickup being bad. With a jumper wire make/break to ground the neg primary terminal on the coil & see if the coil wire now sparks & if so that points to the ECU (& or it's supporting wiring) as the culprit. Have to work fast & get em while they are hot & may need to warm it up between tests. Keep us updated!
Posted By: cjskotni

Re: Electrical Gurus Needed - UPDATE - 11/12/12 05:13 PM

OK I got my toubleshooting in for today. Here is what I found as the car warmed up from cold then died after 15 minutes or so:

- voltage on ignition side of ballast resistor ~14.5V
- volatge on run side of ballast (brown wire) ~ 4.7V
- voltage on + coil terminal (ref to ground) ~ 4.7V

These readings hold pretty steady right up until the motor dies and they do drop slightly but I would guess that is due to the lower idle speed as the engine dies.

Timing light hooked up the entire time to coil wire and seems to be steady spark from coil the entire time. When the engine dies and you try to crank it, it shows RPMs of about 800 or so which would mean 100 RPMs from starter cranking. I would think this is indicative of spark from coil.

The only ignition things left could be dizzy/plugs/wires. I would think if the dist pickup where bad (just replaced - brand new) then the motor would not be getting spark. If the wires or plugs were going, the motor would be missing/popping/surging which is not the case.

I looked in the carb after the motor dies and I can definitely see the pump shot when you blip the throttle (and smell it).

If we assume the gas is still in the bowls (hence the pump shot), wouldn't that mean the carb is sill giving fuel from the jets? If not, what could cause this to stop?? This is just venturi effect which "pulls" the gas from the jets basically...right?

I just can't fathom this being a carb issue with it ruuning so well and then dying after 15 minutes like clockwork. Can anything in the carb even cause this??
Posted By: hooziewhatsit

Re: Electrical Gurus Needed - UPDATE - 11/12/12 05:39 PM

Unplug the coil wire at the distributor, and wedge it somewhere that holds it 1/4" from a ground point. Crank the engine and see what the spark look likes.

Do this again after it dies and make sure the spark looks the same. I wouldn't necessarily trust just a timing light on the coil wire as an indicator of good spark.

You can also disconnect the two pin plug from the ECU to the distributor, then tap the male terminal on the ECU side to ground (morse-code style), and you should get a shower of sparks from the coil wire.


Have you check the reluctor gap recently? I had a new disty I gapped, then over the next week I went from good start to hard start to no start. The gap had opened itself up to ~0.040"+
Posted By: cjskotni

Re: Electrical Gurus Needed - UPDATE - 11/12/12 06:13 PM

Quote:

Unplug the coil wire at the distributor, and wedge it somewhere that holds it 1/4" from a ground point. Crank the engine and see what the spark look likes.

Do this again after it dies and make sure the spark looks the same. I wouldn't necessarily trust just a timing light on the coil wire as an indicator of good spark.

You can also disconnect the two pin plug from the ECU to the distributor, then tap the male terminal on the ECU side to ground (morse-code style), and you should get a shower of sparks from the coil wire.


Have you check the reluctor gap recently? I had a new disty I gapped, then over the next week I went from good start to hard start to no start. The gap had opened itself up to ~0.040"+



When you tap the 2 pin pickup connector to ground, should this be without the coil to distributor wire disconnected? I am guessing you are trying to simulate the pickup signal and "trick" the ECU into firing the coil...

I will also check the reluctor gap as you suggested.
Posted By: cjskotni

Re: Electrical Gurus Needed - UPDATE - 11/12/12 08:03 PM

I went ahead, took some old parts back, and bit the bullet and purchased a brand new MSD Blaster II coil....the exact same model I had.

Fired the car up and died after about 15 minutes again BUT I could restart it with some degree of effort. Once restarted, I hooked up a spark tester to the #7 wire and this is what I see:

- 10K volts: consistant spark
- 20K volts: seems to lose maybe 20% of the sparks?
- 30K volts: maybe get 20% of the sparks losing 80+% very inconsistant

This is a advertised 45K volt coil. I would think I should be getting more energy than that at the plug. I guess I will have to repeat with a cold motor.

BTW when I crank it with the tester on, you can definitley see a MUCH brighter spark as would be expected.

If I am getting a large secondary voltage drop between coil and plugs, I guess I am down to dizzy and wires now...would ECU weaken spark? I have a new one of those I can swap back -- maybe I can try later...

At least maybe some change in the right direction...
Posted By: Swedcharger67

Re: Electrical Gurus Needed - UPDATE - 11/12/12 08:30 PM

I think it goes back to the previous step, if you don't have all "juice" in on the primary winding in the coil...you don't get all juice out from the secondary winding to the spark plugs.
I would still look for the reason why you have that low 11.something volts in to ballast resistor and corresponding low voltage (= low current = low energy = weak spark) to the coil.
Posted By: moparmarks

Re: Electrical Gurus Needed - UPDATE - 11/12/12 08:55 PM

Don't think you use a ballast resisitor with a MSD coil. Check the instrutions.
Posted By: cjskotni

Re: Electrical Gurus Needed - UPDATE - 11/12/12 09:36 PM

Quote:

I think it goes back to the previous step, if you don't have all "juice" in on the primary winding in the coil...you don't get all juice out from the secondary winding to the spark plugs.
I would still look for the reason why you have that low 11.something volts in to ballast resistor and corresponding low voltage (= low current = low energy = weak spark) to the coil.



The 11.something reading was with the engine OFF. With the motor running, the reading on the blue wire of the ballast is 14+V.

Quote:

Don't think you use a ballast resisitor with a MSD coil. Check the instrutions.




I will read the instructions but I have run this exact coil for a LONG time with ballast and no issues like this. Maybe I could ditch it but I don't think it is necessary to run without one. If this had been the case from day one, I'd agree with you but this problem began with a perfectly running car. I even had it dynoed with this exact same setup before this began...
Posted By: Swedcharger67

Re: Electrical Gurus Needed - UPDATE - 11/12/12 10:42 PM

Quote:


The 11.something reading was with the engine OFF. With the motor running, the reading on the blue wire of the ballast is 14+V.



A normal, fully charged battery should hold 12.8 volts.
Your ignition system will draw 3.6 amps (only!) and your voltage feed to the ballast & coil drops to 11.something...there is something that doesn't add up...
Posted By: coronetville

Re: Electrical Gurus Needed - UPDATE - 11/12/12 11:02 PM

run a new ground wire to ecu, if that doesnt work replace ballest res. if that doesnt work replace ecu. before going nuts on wiring If you upgraded with a 100 amp alt you have to upgrade alt. wiring
Posted By: cjskotni

Re: Electrical Gurus Needed - UPDATE - 11/12/12 11:12 PM

Quote:

Quote:


The 11.something reading was with the engine OFF. With the motor running, the reading on the blue wire of the ballast is 14+V.



A normal, fully charged battery should hold 12.8 volts.
Your ignition system will draw 3.6 amps (only!) and your voltage feed to the ballast & coil drops to 11.something...there is something that doesn't add up...



Voltage at battery is ~12.7V (not fully charged from cranking), voltage @ black pin on ign switch harness is ~12.25V, voltage at blue pin of ign switch harness is ~12.05V.

Looks like I am losing about .4 volt on each bulkhead connections (and wire run) and about 1/4 volt on the ignition switch itself. This would account for the difference. However running it's 14+V @ the ballast so I think that's OK.

I agree it seems high but those connections are CLEAN and packed with dialectric grease. I dn't see it getting much better...

Can anybody here tell me what a "healthy" spark voltage to have is at the plugs? The consistant 10KV I am getting seems low. Would this be low enough to cause my engine dying problem?

I would think even with OEM coil, I would be getting a solid 15-20KV at least...
Posted By: Sinitro

Re: Electrical Gurus Needed - UPDATE - 11/13/12 05:19 AM

Quote:

Quote:

Quote:


The 11.something reading was with the engine OFF. With the motor running, the reading on the blue wire of the ballast is 14+V.



A normal, fully charged battery should hold 12.8 volts.
Your ignition system will draw 3.6 amps (only!) and your voltage feed to the ballast & coil drops to 11.something...there is something that doesn't add up...



Voltage at battery is ~12.7V (not fully charged from cranking), voltage @ black pin on ign switch harness is ~12.25V, voltage at blue pin of ign switch harness is ~12.05V.

Looks like I am losing about .4 volt on each bulkhead connections (and wire run) and about 1/4 volt on the ignition switch itself. This would account for the difference. However running it's 14+V @ the ballast so I think that's OK.

I agree it seems high but those connections are CLEAN and packed with dialectric grease. I dn't see it getting much better...




Having the bulkhead connections, kleen and packed with dia-lectric grease are (2) of the 3 requirements...
The other one is being tite..

The female tab 0.25" tab connector on the firewall side must grip the male side titely...
After 45 years these connections can be marginal and it doesn't take much to lose the required voltage. What I normally do is to insert a small pair of needle nose pliers and crimp down slightly on the female side...

Just my $0.02...
Posted By: hooziewhatsit

Re: Electrical Gurus Needed - UPDATE - 11/13/12 07:13 AM

Quote:

When you tap the 2 pin pickup connector to ground, should this be without the coil to distributor wire disconnected? I am guessing you are trying to simulate the pickup signal and "trick" the ECU into firing the coil...

I will also check the reluctor gap as you suggested.



During this test you'll still have the coil wire off the distributor and 1/4" from a ground point. And yes, this tricks the ECU into firing the coil.

In my case, I had weak/no spark while cranking (gap too large), but had an avalanche of HUGE sparks when I tapped the plug to ground.

If it dies and you have good spark with this test, then it shows the ECU side is ok, and narrows the problem to the pickup side.

You might also jump battery voltage around the bulkhead/ignition switch to make sure you have good voltage to the ECU/BR.
Posted By: jeff500

Re: Electrical Gurus Needed - Wierd Ignition Issue!! - 11/13/12 11:18 AM

I don't think there's anything wrong with your wireing,it is the pickup coil in the dizzy. Pull the dist out and put in another one............problem solved.
Posted By: cjskotni

Re: Electrical Gurus Needed - UPDATE - 11/13/12 02:44 PM

Quote:

Quote:

When you tap the 2 pin pickup connector to ground, should this be without the coil to distributor wire disconnected? I am guessing you are trying to simulate the pickup signal and "trick" the ECU into firing the coil...

I will also check the reluctor gap as you suggested.



During this test you'll still have the coil wire off the distributor and 1/4" from a ground point. And yes, this tricks the ECU into firing the coil.

In my case, I had weak/no spark while cranking (gap too large), but had an avalanche of HUGE sparks when I tapped the plug to ground.

If it dies and you have good spark with this test, then it shows the ECU side is ok, and narrows the problem to the pickup side.

You might also jump battery voltage around the bulkhead/ignition switch to make sure you have good voltage to the ECU/BR.



I will try this test next time I have a block of time to crank her up again. Thanks for the information! Another thing I might try aftre the motor dies is jump (for a limited time) from the + terminal on battery to the + terminal on the coil to give it full voltage. Would this harm the coil if I had this on for a few minutes? I just don't want to cook my coil. :-(

I would assume if this worked, it points to weak spark which would indicate and ECU/wiring/coil issue. Sicne I am getting a consitant spark at the plug (after motor dies), I am guessing puckup is OK. The pickup indirectly controls when and IF the coil fires but not the magnitude of the spark itself or am I wrong?

It just seems odd I am only getting a consistant spark at 10kV or less. When I widen the tester gap to 20kV or higher the spark becomes very inconsistant. My memory could be failing me here but I seem to remember this motor (and other stock engines of various makes) having no trouble arching across the tester at 20-30kV.

Quote:

I don't think there's anything wrong with your wireing,it is the pickup coil in the dizzy. Pull the dist out and put in another one............problem solved.




I would agree with you but I installed a brand new pickup last month. No change.
Posted By: Swedcharger67

Re: Electrical Gurus Needed - UPDATE - 11/13/12 04:06 PM

Quote:


It just seems odd I am only getting a consistant spark at 10kV or less. When I widen the tester gap to 20kV or higher the spark becomes very inconsistant.


Nothing strange at all, if you have too little into the coil, you will have too little out from the coil.
Posted By: 71_deputy

Re: Electrical Gurus Needed - UPDATE - 11/13/12 05:49 PM

note- what if the wires from the dist. are wired in reverse??? I have heard of this before with a brand new harness/ dist.?????

try to make a tempoary pigtail without cutting the existing wiring!!!
Posted By: dvw

Re: Electrical Gurus Needed - UPDATE - 11/14/12 02:24 AM

Not that this may be related. Pump shot does not mean the bowl is full. The pump retains fuel in the pump reservoir after the bowl goes dry. Granted it should at least fire up on pump shot for a second or so. I still contend check the wiring with a headlamp bulb. the bulb pulls enough amperage to show a weak connection. Not very high tech but it works.
Doug
Posted By: cjskotni

Re: Electrical Gurus Needed - UPDATE - 11/14/12 03:02 AM

Thanks for all the ideas guys, I appreciate the suggestions so far.

I managed to get out in the garage again today and with the new coil in, I got it to run for about 45 minutes straight while I tested various voltages, etc.

It seems the motor is fine (doesn't drop idle speed) if the voltage on the high side of the coil stays above ~4V. I noticed that with the fans on @ in-gear idle, the voltage on the coil starts dropping to 3.8-3.9V which makes the engine idle lower (weaker) which spins the alternator less which lowers the voltage and so on until it dies.

I went ahead and fiddled with the engine harness bulkhead connector and the ignition switch harness to dash harness connection and managed to get an extra .2V or so on the ignition side of the ballast which gave a lil more "oomph" to the coil. With that little bit extra the engine stayed running MUCH longer and didn't die on me. I measured all the volatges and I am seeing a net loss of only .8V from + battery terminal to ballast now.

I am guessing the issue may be the Blaster II coil I have "wants" more voltage (and current) than the stock coil would. My ballast resistor is sitting at near 2 ohms across it which is dropping the voltage from 14+ to 4 volts on coil or so which is marginal from what I see. I ordered an Accel ballast which is supposed to .65 ohms and a Mopar ballast which is supposed to be 1.4 ohms. I am going to try both of these to see if I can't get some more voltage and current on that coil. BTW, the ballast they recommend for this coil (and, yes it SHOULD have one) is .85 ohms. I am hoping by getting rid of some of the voltage drop on the ballast I can better "feed" this coil even if the alternator drops to 700 RPM in gear and falls behind.

I also found that the brown pin on the brand new M&H dash harness I have was pushed back out of the Molex connector probably causing a weak connector on the start circuit. I fixed this and packed that connector with dielectric grease as well. This helped with some of the voltage drop I was seeing.

Hopefully I will get the new ballasts in by this weekend and I can fill everyone in on if this helps my issue.

Does anybody else here run a Blaster II coil with the MP Elec Ign? If so, can you tell me what your MSD coil "likes" as far as voltage goes and/or what ballast you run?

Quote:

During this test you'll still have the coil wire off the distributor and 1/4" from a ground point. And yes, this tricks the ECU into firing the coil.

In my case, I had weak/no spark while cranking (gap too large), but had an avalanche of HUGE sparks when I tapped the plug to ground.

If it dies and you have good spark with this test, then it shows the ECU side is ok, and narrows the problem to the pickup side.

You might also jump battery voltage around the bulkhead/ignition switch to make sure you have good voltage to the ECU/BR.




I did this test with engine hot and cold. Both times getting good spark! I used a spark plug tester to connect the coil wire to ground and a remote starter to jump the pickup connector to ground. Worked like a charm and I could see the strength of the spark! With the engine not running, I was getting 20-25 kV of juice! So I guess this means coil and ECU are good?

Thanks again to all you guys for you help and suggestions!!
Posted By: Sinitro

Re: Electrical Gurus Needed - UPDATE - 11/14/12 03:33 AM

Quote:

Thanks for all the ideas guys, I appreciate the suggestions so far.

I managed to get out in the garage again today and with the new coil in, I got it to run for about 45 minutes straight while I tested various voltages, etc.

It seems the motor is fine (doesn't drop idle speed) if the voltage on the high side of the coil stays above ~4V. I noticed that with the fans on @ in-gear idle, the voltage on the coil starts dropping to 3.8-3.9V which makes the engine idle lower (weaker) which spins the alternator less which lowers the voltage and so on until it dies.

I went ahead and fiddled with the engine harness bulkhead connector and the ignition switch harness to dash harness connection and managed to get an extra .2V or so on the ignition side of the ballast which gave a lil more "oomph" to the coil. With that little bit extra the engine stayed running MUCH longer and didn't die on me. I measured all the volatges and I am seeing a net loss of only .8V from + battery terminal to ballast now.

I am guessing the issue may be the Blaster II coil I have "wants" more voltage (and current) than the stock coil would. My ballast resistor is sitting at near 2 ohms across it which is dropping the voltage from 14+ to 4 volts on coil or so which is marginal from what I see. I ordered an Accel ballast which is supposed to .65 ohms and a Mopar ballast which is supposed to be 1.4 ohms. I am going to try both of these to see if I can't get some more voltage and current on that coil. BTW, the ballast they recommend for this coil (and, yes it SHOULD have one) is .85 ohms. I am hoping by getting rid of some of the voltage drop on the ballast I can better "feed" this coil even if the alternator drops to 700 RPM in gear and falls behind.

I also found that the brown pin on the brand new M&H dash harness I have was pushed back out of the Molex connector probably causing a weak connector on the start circuit. I fixed this and packed that connector with dielectric grease as well. This helped with some of the voltage drop I was seeing.

Hopefully I will get the new ballasts in by this weekend and I can fill everyone in on if this helps my issue.

Does anybody else here run a Blaster II coil with the MP Elec Ign? If so, can you tell me what your MSD coil "likes" as far as voltage goes and/or what ballast you run?

Quote:

During this test you'll still have the coil wire off the distributor and 1/4" from a ground point. And yes, this tricks the ECU into firing the coil.

In my case, I had weak/no spark while cranking (gap too large), but had an avalanche of HUGE sparks when I tapped the plug to ground.

If it dies and you have good spark with this test, then it shows the ECU side is ok, and narrows the problem to the pickup side.

You might also jump battery voltage around the bulkhead/ignition switch to make sure you have good voltage to the ECU/BR.




I did this test with engine hot and cold. Both times getting good spark! I used a spark plug tester to connect the coil wire to ground and a remote starter to jump the pickup connector to ground. Worked like a charm and I could see the strength of the spark! With the engine not running, I was getting 20-25 kV of juice! So I guess this means coil and ECU are good?

Thanks again to all you guys for you help and suggestions!!



According to the Mopar Performance catalog..
When using a Blaster coil, the correct ballast resistor value is 0.25 Ohms which is Mopar #P2444641. A higher value ballast resistor will greatly decrease the primary voltage to the coil and its respective HV output...


Just my $0.02..
Posted By: stumpy

Re: Electrical Gurus Needed - UPDATE - 11/14/12 03:41 AM

Are you using relays on the fans etc?
Posted By: cjskotni

Re: Electrical Gurus Needed - UPDATE - 11/15/12 01:46 AM

Quote:

Are you using relays on the fans etc?



Yes I am using relays for each of the fans and the A/C as well.
Posted By: stumpy

Re: Electrical Gurus Needed - UPDATE - 11/15/12 04:39 AM

Where are you pulling the 12v for the fans from?
Posted By: ThermoQuad

Re: Electrical Gurus Needed - UPDATE - 11/15/12 04:58 AM

Let's try some troubleshooting instead of mud slinging.

If your ignition switch is from 1973 we are all wasting out time here as this is classic symptoms of a bad ign switch. OK????

Voltage tests should be done when the car is running.

When the car is running there should be 13.8-14.4 volts across the battery terminals and 7-9 volts at the coil. Period.

Pick a ballast resistor that puts the coil voltage at 9 volts.

If you want to get technical E=IR
E being volts I the current & R the resistance

As soon as the car dies measure the voltage at the coil. 7 volts or more is what i would expect to see.

Next unplug the distributor pick up and put the leads across the terminals going to the dist. Crank the engine and meter should be changing state-ie going from OL [over limit] to a reading in ohms...Pick up is working if meter is changing state, the number is not important.

There should be several grounds from the body to the engine including one from the control box to the engine.

Post a pic of your grounds and control box set up
Posted By: cjskotni

Re: Electrical Gurus Needed - UPDATE - 11/15/12 12:35 PM

Quote:

Let's try some troubleshooting instead of mud slinging.

If your ignition switch is from 1973 we are all wasting out time here as this is classic symptoms of a bad ign switch. OK????

Voltage tests should be done when the car is running.

When the car is running there should be 13.8-14.4 volts across the battery terminals and 7-9 volts at the coil. Period.

Pick a ballast resistor that puts the coil voltage at 9 volts.




The previous ignition switch was about 6 years old and I just replaced it with a brand new one. Voltage drop across the switch is ~0.2V.

With the motor running with fans off, voltage is near 15V and with fans on, drops to around 14.2-14.4V or so. This translates to a volatge on the ignition side of the ballast of ~13.8-14V.

I think you are correct when you say the issue is the ballast. The ballast is only leaving 4.2V on the hi side of the coil once the fans are on. When you put the car in gear and the idle drops to ~700 RPM, the coil voltage starts falling below 4V and thats when the idle starts dying.

I have two ballasts on order with lower resistances. I will measure them when they arrive and fill everyone in on how they work!
Posted By: mopar_man

Re: Electrical Gurus Needed - UPDATE - 11/15/12 02:39 PM

Ok first post on this problem .

Problem: engine dies after 15 mins. or so
Problem: haven't isolated the whats causing this.

Here's what I would do to isolate harness and ign. system .
Disconnect wires from + side of coil.
Run two wires from battery to + terminal on coil . one wire with an in line ballast resistor . start car and remove solid wire so you don't cook the coil
if the engine still dies, you have very little wireing and parts to look at ........
I would unhook your alt. just for the test .

Now if the engine still dies , your down to coil, ecm , dist and carb/fuel .
see what happens .
Posted By: cjskotni

Re: Electrical Gurus Needed - UPDATE - 11/15/12 06:34 PM

Quote:

Ok first post on this problem .

Problem: engine dies after 15 mins. or so
Problem: haven't isolated the whats causing this.

Here's what I would do to isolate harness and ign. system .
Disconnect wires from + side of coil.
Run two wires from battery to + terminal on coil . one wire with an in line ballast resistor . start car and remove solid wire so you don't cook the coil
if the engine still dies, you have very little wireing and parts to look at ........
I would unhook your alt. just for the test .

Now if the engine still dies , your down to coil, ecm , dist and carb/fuel .
see what happens .



I am thinking we **may** have found the issue when I saw that when the coil voltagge drops below ~4V the idle becomes rough and begins to lower which drops the voltage more and death spirals the motor.

With the fans on and in park the idle is about 800 RPM which keeps the coil voltage at 4.2V which is enough to keep her alive. Once I get below around 750, the alternator isn't keeping enougg voltage which begins this process.

I troubleshot the wiring and I am seeing voltage drop of almost 10V on the OEM ballast I have which is too much for my Blaster coil apparently.

I am guessing with the everything cooled off, I am right on the verge of too weak of a spark but the heat from the motor running may have pushed it over the edge raising resistance in the ballast/wiring.

Not sure why I ran OK before but this started about two months ago. Maybe I was just marginal the entire time and I just stepped over the edge?

I am hoping my theory here is correct as I have about troubleshot the hell outta this ignition system!

If this doesn't work, I will be trying your test along with others...
Posted By: 70plumrt

Re: Electrical Gurus Needed - UPDATE - 11/15/12 11:23 PM

I had a Ram that would die after 20 mins.
When I'd take it to the mechanic it would work fine.
The next day same thing!
After the third time he drove it till it stalled on him and wouldn't restart.
Turned out the fuel pump was over heating!



Funny thing was a different mechanic thought it needed a whole new full exhaust system!

Posted By: Rick_Ehrenberg

Re: Electrical Gurus Needed - UPDATE - 11/16/12 05:41 AM

Quote:

...If you upgraded with a 100 amp alt you have to upgrade alt. wiring



Amen to that! This is a meltdown waiting to happen.

Rick
Posted By: cjskotni

Re: Electrical Gurus Needed - UPDATE - 11/16/12 03:42 PM

Quote:

Quote:

...If you upgraded with a 100 amp alt you have to upgrade alt. wiring



Amen to that! This is a meltdown waiting to happen.

Rick



I respectfully disagree! The way I have my fans wired, it is no more likely to "meltdown" than a factory setup.

I take the fan relay feeds directly from the alt stud so while the car is running, no fan current goes through the bulkhead/ammeter charging circuit! The only point where the 20 amp draw of the fans would go through the entire charge circuit is when it fulls from battery (car off). I doubt that a couple of seconds of 20 amp draw when the car is off would burn up the OEM wires which are all brand new in my case. :-)

Also a common misconecption is that a hi output alternator will push those extra amps through the charging circuit. The car/battery will only "take" what it needs (ohm's law). The only difference is that the hi output alternator will be able to "hold" a higher voltage given a lower resistance (more load/accessories ON) than the OEM 60 amp unit.

The issues where people are burning up their cars with hi-output units is where they tap into 12V power from the starter relay or battery terminal whitch DOES pull the extra current for those extra accessories (fuel pump/fans/etc) through the entire engine/dash harness while the car runs.

It also doesn't help if you have 40+ yr old wires and they are dirty and corroded....not to mention the factory didn't build much margin into the charging circuit as we all know.

Not a bad idea to upgrade the wiring but not necessary if wired/maintained correctly.
Posted By: Pyper70

Re: Electrical Gurus Needed - UPDATE - 11/16/12 07:37 PM

Sounds like your fusible link is overloading with driving time and it blows out and shuts your car down. After a while the Fusible link "resets" and you are back on your way until you shut down again right? Are you sure the new Fusible Link is of equal or greater value since you claim to have a new harness. I removed my fusible link from my systems when I upgraded to MSD and a larger alternator. I ran the PowerMaster 120a Single wire straight to the batter with a 6 GA. cable. remove your ballast resistor as that is designed to use a lower voltage coil, not needed with a Blaster coil or MP coil. All those cables from the ballast resistor get fused together I think with a wire nut. I put an inline fuse where the fusible link would be and put on a 25a fuse...then a 35a...then a 40a...thats with everything on....the heater, the stereo system, the headlights, the everything..I ended up replacing the 40a fuse with a 40a reset breaker from a 737 cockpit (my friend worked at SAGE Air...) big red button on the firewall...looked clean...people never knew what it was. Never blew another fusible link.

One other thing to check is the Starter relay...it supplies your cabin with all the necessary power...if it heats up from a bad ground or a leak in the circuitry...you will blow the fusible as well..

And finally, the only other time my Charger has slow blown a fuse was when the wiring for the power seat ended up getting grounded to the floorpan because the shielding came off the cable..I was driving to Vegas at 3am...stopped for gas 3 hours out...and she wouldn't let me leave the gas station until I dragged her to an electrical shop by tow truck and he found the broken wire under the carpet.
Posted By: 3twos

Re: Electrical Gurus Needed - UPDATE - 11/16/12 07:50 PM

I think 2 ohms is way too much. Also I seem to remeber the blaster 2 coil should use a .8 ohms resistor?
Posted By: Sinitro

Re: Electrical Gurus Needed - UPDATE - 11/16/12 08:33 PM

Quote:

I think 2 ohms is way too much. Also I seem to remeber the blaster 2 coil should use a .8 ohms resistor?



According to the Mopar Performance catalog..
When using a Blaster coil, the correct ballast resistor value is 0.25 Ohms which is Mopar #P2444641.


Just my $0.02..
Posted By: stumpy

Re: Electrical Gurus Needed - UPDATE - 11/16/12 08:53 PM

When a fusible link blows it's gone. There is no reset to it just like a regular fuse.
Posted By: cjskotni

Re: Electrical Gurus Needed - UPDATE - 11/16/12 09:56 PM

Quote:

When a fusible link blows it's gone. There is no reset to it just like a regular fuse.



It's not the fusible link or a break in the charging circuit. With the ammeter, it will die when I have a neatral charging situation (niether charge or discharge).

I am pretty sure its a low volatge condition on my coil from the OEM ballast.
Posted By: 3twos

Re: Electrical Gurus Needed - UPDATE - 11/16/12 10:49 PM

Quote:

Quote:

I think 2 ohms is way too much. Also I seem to remeber the blaster 2 coil should use a .8 ohms resistor?



According to the Mopar Performance catalog..
When using a Blaster coil, the correct ballast resistor value is 0.25 Ohms which is Mopar #P2444641.

Good advice, take the 2 ohm resistor and pitch it.



Just my $0.02..

Posted By: cjskotni

Re: Electrical Gurus Needed ***Progress Finally*** - 11/17/12 05:34 PM

Guys,

Well I purchased the MSD .08ohm ballast that is what their documents suggest to use with the Blaster coil. Now I get between 7.5V to 8.5V on the coil!

I cranked her up and ran for 25 minutes or so, no shutting off. I don't know if I will have the chance to take her for a spin this weekend and I am a little gun-shy now of being stranded for the 4th time with this issue!

Idle still drops about 20 RPM when the fans kick on at idle but I would imagine that's normal as the alternator is now putting up some resistance on the belts with the new 20 amp load. However I idled in gear with fans for 6 or 7 minutes and idle held steady around 700-720RPMs.

An interesting note is that whatever I seem to set the curb idle to out of gear (750-850+ RPMs) does not seem to make much difference to what the engine settles at in-gear (always 700-720 RPMs). I do see a difference in how fast the car moves at idle when I let the brake go but that's it.

Is that normal? I don't want to set my curb idle to any more than 850RPM but I was wondering if that might help keep the in-gear idle a bit higher to keep this problem at bay....apparently not.

Oh and by the way, thanks for everyone's input here so far! It is nice to see people taking the time to help a fellow hobbyist here

I will keep posted if the issue rears its ugly head again.
Posted By: cjskotni

Re: Electrical Gurus Needed ***Progress Finally*** - 11/18/12 12:01 AM

Well I got some unexpected time today and took the Charger out for a spin. I made it to the gas station to top her off and back. I noticed that it was running a bit rough so I let it keep idling after I got home and it did eventually idle down and die.

Voltage never got below 7V on the hi side of the coil so not a voltage is not an issue.

Immediatley after it died, I grounded the ECU harness and checked for spark on the coil wire and I am getting a consistant 35kV+ spark!

I then reconnected everything and fired it back up with minimal effort. Car died about 2 or 3 minutes after this. Can restart and same happens.

SO the issue is still there but better now? Car will run for longer before dying and can be re-started unlike before where there was no starting it until it cooled off completely.

I am open to any suggestions. I would say maybe a fuel issue but it can fire back up and run for a few minutes. I would think if the carb were not delivering, it would run very rough and or pop with it leaning out. Not the case....runs fine until it dies.

Since the coil is giving plenty of spark when ECU is triggered I guess I am down to the dizzy/wires/plugs??
Posted By: cjskotni

Re: Electrical Gurus Needed ***Progress Finally*** - 11/18/12 03:01 PM

Ok guys,

Another update here. I decided last night to check the fuel filter and sure enough it was significantly gunked with debris. I assumed this was ok becuase I cleaned it out when I had the car dyno'ed in August and I have had very little run time since then.

I think this may be part of the issue for sure. I know somebody here said to check the carb for fuel so on that suggestion!

Seems a little bit different from normal fuel filter issues where it just clogs and that's the end of it, no/poor running until it's fixed...not run for 15-25 minutes then die...

I will try to test and let you know how it goes!

Attached picture 7466393-gunk.jpg
Posted By: jlatessa

Re: Electrical Gurus Needed ***Progress Finally*** - 11/18/12 06:35 PM

Maybe I'm smarter than I look, probably a good thing too!!

Joe
Posted By: cjskotni

Re: Electrical Gurus Needed ***Progress Finally*** - 11/19/12 02:29 AM

I took the primary fuel bowl off and metering block and blew them off really good with carb cleaner. I also took out the idle mix screws and blew those passages out with the cleaner.

Anything else I should do? The fuel bowl and metering black had significant rusty silt in them.

I have no idea where all this came from! The gas tank was replaced 4 or 5 years ago with along with new SS lines. This car has been under resto almost since. I tore down the carb and cleaned it out not a few months ago! To say this is annoying is an understatement!
Posted By: moparmarks

Re: Electrical Gurus Needed ***Progress Finally*** - 11/19/12 02:45 AM

Sounded more like a fuel rather than an Ing problem. Was going to say that you needed to pump the accel pump a few times to make sure the carb still had fuel. Not just once.
Atleast spary and blow out the passages in the airhorn[body]. That crap is probably in the sec bowl and the pumps too so may want to pull that bowl. May want to just do a re-build.
Posted By: RapidRobert

Re: Electrical Gurus Needed ***Progress Finally*** - 11/19/12 06:04 AM

Quote:

Anything else I should do?

I'd strip the rest of the carb & blow it out good with spray cleaner then with shop air then button her up & put a good filter between the mech pump and the carb & see how it acts. My fingers are crossed on this one
Posted By: edp

Re: Electrical Gurus Needed ***Progress Finally*** - 11/19/12 06:14 AM

why not disconnect the main fuel line from the intake side of the pump & hook up a line to a 5 gallon gas can & let it run - then you'll of isolated the tank & lines out of the system.

If it still dies you'll know its in the carb, pump & filter.....
Posted By: cjskotni

Re: Electrical Gurus Needed ***Progress Finally*** - 11/19/12 02:46 PM

I cleaned up the primary side of the carb and buttoned her back up just to test. Holy chitterlins, she runs different!

- hot start is SO MUCH easier now - just fires right up
- same curb idle, when I drop it into gear idle drops to like 730-750 RPM...not the 690-710 I was seeing before
- RPMs don't drop as much when fans kick on

I ran it for 25 minutes or so this morning like this and not even a sign of cutting off from what I could see. I am thinking maybe it was getting partially fuel starved and when the motor was loaded with alternator draw and especially in gear, it began to starve a bit.

I am thinking maybe I had a dual issue here with the dirt carb/fuel filter being the primary issue and the low coil voltage makeing the problem worse. After the replacing the ballast and getting the coil voltage up, the issue was much better but still was there.

I wonder how much HP I lost on the dyno from a weak spark? I was only getting a consistant 10-15kV at the plugs before and didn't know it until now . Now I am sitting at 35kV+ with the ignition tune-up I have done while troubleshooting this issue.

Needless to say this issue will probably come back if I have crap in the tank. When I get this car back in a driveable state, I will take it to have the tank flushed I guess. I want to know where all this crap came from!?

I will also probabaly go through the carb better and clean the secondary side as well to make sure this doesn't happen again.

As far as fuel filters go, I have the billet aluminum in-line with the 40 micron SS mesh filter. Is this not a good idea to use? It keeps the big stuff out but obviously the silt is still getting through. I have 6AN female fittings on both sides so I really don't want to have to ditch those if possible....

Thanks for all your help and ideas guys!
Posted By: RapidRobert

Re: Electrical Gurus Needed ***Progress Finally*** - 11/19/12 03:08 PM

You sound pumped . I was beginning to think this one would go unsolved! If the ballast was the only (electrical) part changed you might swap the old one back in for a 5 minute test just to pin things down even further & it'd be a piece of cake to do. I'd suggest a 10 micron high flow filter between the mech pump/carb & a 100 micron high flow filter ahead of the electric pump if an electric pump is being used. Definitely flush the tank/lines
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