starting problems

Posted By: AB&E

starting problems - 02/23/11 07:53 PM

I have a 70 cuda. electronic ignition running the orange box just recently it will not start untill you realease the key & catch it just right it will fire up. but it will not start when cranking over only when you go to stop cranking will it fire up if you time it right. is it ignition switch or ?????

Posted By: DaytonaTurbo

Re: starting problems - 02/23/11 07:57 PM

Check your ballast resistor. If it's a 4-pin ballast resistor, it has one circuit for crank and the other one is for run. To test it out, just temporarily hook all 4 wires together, bypass the ballast completely. If it starts during the crank cycle now, you know your ballast is shot. If that doesn't do it, swap in a spare ecu.

Posted By: RapidRobert

Re: starting problems - 02/24/11 01:30 AM

See if you have fire at the brown wire end of the ballast in "start" & if not trace it back to the bulkhead on the firewall & open the bulkhead & see if that particular brass terminal pair is not corroded and that the brass terminal half on the cabin side has fire in "start" & if not go inside to the ign sw & see if the "ST" terminal on the back of it has fire in "start" EDIT meant "ign2" terminal

Posted By: therocks

Re: starting problems - 02/24/11 03:10 PM

Typically the ballast is either bad or good.No inbetweens.Id say its the ignition switch.Sounds like its sometimes hitting the power spot and sometimes its not.Rocky

Posted By: Yancy Derringer

Re: starting problems - 02/24/11 03:44 PM

Rapid is correct this is NOT the ballast, which is bypassed during cranking.

More and more, are reports of problems with the "bulkhead connector.

I would suspect the path from the brown bypass circuit and inspect through the bulkhead, the connector on the ign. switch, and the switch itself.

Don't throw parts at it, get a multimeter and do some checking.

Posted By: MoparforLife

Re: starting problems - 02/24/11 04:18 PM

easy to swap a out a couple buck ballast. They are either good or bad -no in between. This is a typical symptom of a faulty ballast.

Posted By: Yancy Derringer

Re: starting problems - 02/24/11 06:45 PM

Quote:

easy to swap a out a couple buck ballast. They are either good or bad -no in between. This is a typical symptom of a faulty ballast.

THIS IS NOT a symptom of a bad ballast

Posted By: MoparforLife

Re: starting problems - 02/24/11 07:01 PM

Quote:

Quote:

easy to swap a out a couple buck ballast. They are either good or bad -no in between. This is a typical symptom of a faulty ballast.

THIS IS NOT a symptom of a bad ballast

OH OK> But have seen several where in the process of spinning the engine and releasing the key the spin happens to hit on the firing circuit just right and the engine starts.If it doesn't hit just right when the key is let off on - no go. Check (replace the ballast)

Posted By: Yancy Derringer

Re: starting problems - 02/25/11 03:00 AM

Quote:

Quote:

Quote:

easy to swap a out a couple buck ballast. They are either good or bad -no in between. This is a typical symptom of a faulty ballast.

THIS IS NOT a symptom of a bad ballast

OH OK> But have seen several where in the process of spinning the engine and releasing the key the spin happens to hit on the firing circuit just right and the engine starts.If it doesn't hit just right when the key is let off on - no go. Check (replace the ballast)

That's not "how it works."

The key "run" circuit goes THROUGH the ballast,

So when you are in "crank" the "bypass" circuit FROM THE KEY feeds hot 12V to the coil.

so you have an "either or" situation.

IF the ballast is BAD, you get a nice hot spark from the "bypass" circuit in crank, and the engine will fire, but quit when released to run

IF the ballast is GOOD, but the start bypass circuit bad, then you'll get low voltage during "crank." This is because the battery is being pulled down by the starter, and the ballast FURTHER drops the voltage to the ignition. So without the bypass circuit, the car may or may not start

So one last time. The way the OP described the problem, it is NOT a ballast problem.

Posted By: MoparforLife

Re: starting problems - 02/25/11 07:37 AM

Quote:

Quote:

Quote:

Quote:

easy to swap a out a couple buck ballast. They are either good or bad -no in between. This is a typical symptom of a faulty ballast.

THIS IS NOT a symptom of a bad ballast

OH OK> But have seen several where in the process of spinning the engine and releasing the key the spin happens to hit on the firing circuit just right and the engine starts.If it doesn't hit just right when the key is let off on - no go. Check (replace the ballast)

That's not "how it works."

The key "run" circuit goes THROUGH the ballast,

So when you are in "crank" the "bypass" circuit FROM THE KEY feeds hot 12V to the coil.

so you have an "either or" situation.

IF the ballast is BAD, you get a nice hot spark from the "bypass" circuit in crank, and the engine will fire, but quit when released to run

IF the ballast is GOOD, but the start bypass circuit bad, then you'll get low voltage during "crank." This is because the battery is being pulled down by the starter, and the ballast FURTHER drops the voltage to the ignition. So without the bypass circuit, the car may or may not start

So one last time. The way the OP described the problem, it is NOT a ballast problem.

All fine and good IF you are not working with a dual ballast resistor with a start side and the start side is the side that is blown out and the run side is good. They can at times catch on the run side if the switch happens to be released at the right time.
Likely Will not be a ballast if using the single ballast resistor system.
Been there done that.

Posted By: Yancy Derringer

Re: starting problems - 02/25/11 06:14 PM

Quote:

All fine and good IF you are not working with a dual ballast resistor with a start side and the start side is the side that is blown out and the run side is good. They can at times catch on the run side if the switch happens to be released at the right time.
Likely Will not be a ballast if using the single ballast resistor system.
Been there done that.

THERE IS NO SUCH THING as

"a start side and a run side" of a "dual ballast."

THAT IS NOT HOW THESE WORK and THERE IS NO OPERATIONAL DIFFERENCE between a "dual" and a "single" ballast

It works EXACTLY as I described above. It does NOT matter whether it's a 2 or 4 terminal ballast.

Please STOP spreading incorrect information

ONE SIDE of a "dual" ballast works exactly as the "single" ballast works and in fact the "coil" side of the "dual" ballast is wired and works exactly the same as if the vehicle had a points type distributor.

THE OTHER SIDE of a "dual" ballast IS USED INTERNALLY by the so called older "5 pin" ECU and has NOTHING TO DO with the run/ start bypass circuit

IN FACT a so called "4 pin" ECU can be plugged into a "dual ballast" harness and it will function just as well. THE ONLY PLACE that the downstream terminal of the "other half" of the dual ballast feeds is the box itself. In a 4 pin ECU it goes to a "dead pin" and does nothing at all

Posted By: plymguy

Re: starting problems - 02/26/11 12:21 AM

Be sure to check all of your connections for looseness and dirt. I had a similar problem with my '67 Fury and it was a poor connection in the ignition wiring at the resistor. It would be ok for a while and then would not start.
John