So we tried again to start this thing. (74 Challenger, Stockish 318, stock ignition) New ECU, wiring has been gone through ad nauseam. I got power at the + primary on the coil and power on the blue/yellow wire on the ecu both with key on run and key on start albeit, the voltage is only 4.8 on the primary + coil and slightly higher on the blue/yellow but assumed this is due to ballast. I get spark from the coil secondary by dragging zigzag connector across a ground and holding coil secondary cable 1/4" from a ground.

However, I got no spark at the spark plug (New rotor, cap and cables). I've triple checked gap at distributor pickup/reluctor. I'm thinking bad pick-up coil. Yes? No?

Thanks,
Scott

Sounds right. You can check resistance on the pickup. I believe it should be around 900-1000 ohms. You might be able to hook a test light to positive and then poke at the leads for the distributor. If it sparks, you have a bad pickup.

Should be closer to 350-550 ohms I believe.

If you are getting sparks in run and in start then all that is left is the dist. next step would be to ohm it. If you have a spare dist in your stash (even if BB or /6) just plug it in & spin it by hand & see if you get sparks

375-425


http://www.moparts.org/Tech/Archive/elec/41.html

do I check the resistance on the connector itself or ground and connector or...? Sorry for my ignorance but this is new territory for me. I'm learning new stuff every time I open the hood Since its essentially the last link in the chain, I would be compelled to just replace it and see if she fires.

Robert, no spares in the dist department

Scott

Been reading about reluctor failures, would that cause a no spark condition?

Scott you're doin fine. you would ohm the metal tip and the recessed terminal on the dist zigzag half. If you mean could the pickup cause a no spark yes cuz the pickup triggers the ECU on when to open the coil primary circuit so the secondary can collapse. the only way the reluctor could go bad was if it broke into pieces like from a collision with the magnet if the adj screw cam loose & let the plate shift

OK, thank Robert, others. Just thinking, Rock Auto has the reluctor for $6 and the mid priced pickup is about $19. If my pickup checks out bad, I will go ahead and get the reluctor too just for peace of mind

As a side note; My local O'Reilly's want $84 for the pickup Rock has the whole dang distributor for less than that!!

Bad news is that its going to be a few weeks before I can try it again. I'm scheduled for back surgery a week from Tues and my "crew" is unavailable before that. Stay tuned tho. I will report back with results next try

tow it here & I'll get it going for you and you can set in a lawn chair & watch (have a bucket of KF chicken with you when you arrive)

Might consider as a last result, but I'm stubborn. I'm going to give it another go!

I hope it fires (up) for you & if not I ain't going anywhere. Be sure & make that original with no wings and plenty of biscuits

Well, bought a new pickup. tested it out of the box and got 292 ohms. (Not installed). Tested old still in dist installed in car and got 409 ohms...

Neither female or male gave a reading when tested with ground (One meter lead on the male/female terminal, other to pickup frame or distributor in the case of the old one.)

Have not tried to start with new installed yet. Just curious that new is outside the range posted here and old just under top of range...

I'm planning to install the new one tomorrow and see if I get a spark at the plug by twisting the dizzy

Thoughts??

Scott

put your VOM on low volts AC & spin the shaft & want ~1 volt. No opinion on the ohms specs you're showing.

Thank again Robert. I know this will be a dumb question but would I want to do this spin test plugged in to harness (ECU)? Key on? Or unplugged?

Scott there are no dumb questions. this is with the dist unplugged/isolated & this is strickly checking what the pickup is generating when the reluctor teeth sweep past the magnet. this is the signal that triggers the ECU. touch your probes to the male/female terminals in the dist half of the zigzag connector & give it real healthy spin

Ok got it! Thanks once again!

OK, ne pickup installed. Here's what I got:

Spin test yields 0.01 to 0.02 with VM set on 20v - 004 to 008 with VM set on 2000m

No spark at the plug still. Question, how close should rotor be to the cap contacts when its installed? just wondering if its a defective rotor?? How many volts should I have at the + terminal on the coil? I have about 4.5v. Also, new pickup coil seems to sit higher on the mounting bracket than old. Only about half of the contact bar lines up with the reluctor points while the old one sat lower so it pretty much lined up even with the reluctor...

Hmmmmm! Having trouble understanding new file attaching method.

First pic is the old coil, second is the new one and last is the my volt meter for reference. Sorry pics loaded sideways. They are not sideways on my puter...

4.5V at the coil ain't enough. Something is wonky with the plate/magnet as there should be 100% if not more full contact. .015" rotor blade tip to cap terminal is ideal but most OE are way more than that but when we get the above squared away you can spin the plugged dist & see if it makes the coil wire held 1/4" away from the intake produce sparks then seperately we can deal with the rotor gap/rotor phasing as that ain't involved in just producing sparks out of the coil. Check that the main full plate is sitting with its notch down (flush/even) on the pin (there are 2 notches so 2 choices) & you are on the right one so the 2 outside mounting screws on the housing line up with the (2) turndown 90 deg holes in the lower plate and that the upper swivel plate with the riveted pickup, that it is set down into flush with the lower plate and the thru pin for this is secured underneath with the triangle "locking" piece