Here's what I was trying to say, Ignition switch START wired right to coil not to the ballast (maybe) I've worked on a 75 but it was 35 years ago.
Pulling my hair out.. Ignition. not starting
- Thread starter pedal2themetal
- Start date
451Mopar
Well-Known Member
What is the condition of the battery cables and ground strap from engine to firewall?
ckessel
Well-Known Member
What do you get for a volt reading at the positive side of the coil when you try to start and then let the key off to the run position?
pedal2themetal
Well-Known Member
HI yes all cables are good .. I don't think the starter would turn it over if the block ground was bad..
thanks
tim
pedal2themetal
Well-Known Member
Hi, Don't know.. I have no volt meter or know how to use one.. I've had one but the instruction were gobbledygook. ..to me. I need just a plain one that only reads volts .. those multi meeters to many settings..
I used to have an old multi test meeter (Tach, Dwell, volts)
thanks
tim
451Mopar
Well-Known Member
It can crank the engine with bad cables, they will just have some additional voltage drop.
Because the ECU is grounded to the Firewall, it is possible to have the block ground and Firewall ground at different potentials (a ground loop problem) if there is no block to firewall ground strap.
Usually, it the ignition wants to fire at the release of the key cranking, it could indicate a ground loop problem.
You could test with jumper cables from battery ground to a good block ground (In addition to the original ground cable), and from block ground to firewall / ECU case?
pedal2themetal
Well-Known Member
HI
451Mopar
Just looked and the stock battery to body ground is stock and solid in the factory spot.. no corrosion rust or anything looks almost new like I've said car only has 76,000 miles on it and hasn't rolled over.
thanks
tim
451Mopar
Just looked and the stock battery to body ground is stock and solid in the factory spot.. no corrosion rust or anything looks almost new like I've said car only has 76,000 miles on it and hasn't rolled over.
thanks
tim
451Mopar
Well-Known Member
Tim, I may have not understood your problem? I don't know what you mean by "Works fine for a while" as compared to "it well turn over great and fast"?
If you are saying it cranks over normally and starts compared to cranks really fast, but does not start? If that is the case, the timing chain may be jumping?
When a timing chain jumps, the engine won't have normal compression, so it will crank real fast and easy. I never had the problem on a Mopar, but several 350 Chevy engines with the nylon toothed cam sprocket.
Do the test light test. Let me know what you find. Then we can move forward.
Doug
Doug
@pedal2themetal - does your car have an alarm?
If so, shut the door, and try to start the engine.
I saw this at the drags one day.
If so, shut the door, and try to start the engine.
I saw this at the drags one day.
YY1
Well-Known Member
Looks like we may need to apply "scientific method".
Isolate and sequentially eliminate any variables.
I agree to make damn sure the ECU is grounded.
Poor ground there could cause all sorts of starting and running issues.
I'd personally use an alligator clip jumper to ground it and leave that in place for the remainder of the testing.
Isolate and sequentially eliminate any variables.
I agree to make damn sure the ECU is grounded.
Poor ground there could cause all sorts of starting and running issues.
I'd personally use an alligator clip jumper to ground it and leave that in place for the remainder of the testing.
YY1
Well-Known Member
If the OP jumps the coil to the battery and then jumps the relay (with a known good ground on the ECU), the car should in theory start and continue to run until the jumper to the coil is removed.
If it does not, there is a bigger issue, as that basically bypasses all the system that could be involved in "the problem".
If it does not, there is a bigger issue, as that basically bypasses all the system that could be involved in "the problem".
pedal2themetal
Well-Known Member
YY1
Well-Known Member
...but does it have a seat belt interlock?
It is my understanding that it's a 74 only thing on account of pissing many a customer off.
Look for a metal and plastic strip with wires coming out of it, in the springs under the driver's seat.
...and a plastic box with a red button on it on the firewall near the starter relay and brake booster.
It is my understanding that it's a 74 only thing on account of pissing many a customer off.
Look for a metal and plastic strip with wires coming out of it, in the springs under the driver's seat.
...and a plastic box with a red button on it on the firewall near the starter relay and brake booster.
pedal2themetal
Well-Known Member
Hi
Motor only has 20,000 on full rebuild.. runs fine like a top when it starts (Smokes the tires, er tire.. LOL)... When I said it turns over fast I just mean there is no problem with it not turning.. it just doesn't fire all the time.
I looked at it again last night and one of the shops did add an extra ground to the icu to the battery and the connection does not look that good at the battery.. I'm going to redo it today and see how it does.. be later today..
Thanks , take care be safe
tim
pedal2themetal
Well-Known Member
pedal2themetal
Well-Known Member
HI I hadn't done anything to it and the damn thing has started every time today...
I'm still going to redo that extra ground wire to the ICU. I did also find a loose black wire hanging close to the starter relay it goes into the factory loom set?? not sure what it came from??
the only thing that hasn't been replaced is the starter relay. Maybe that's the problem??
thanks
take care, be safe
tim
I'm still going to redo that extra ground wire to the ICU. I did also find a loose black wire hanging close to the starter relay it goes into the factory loom set?? not sure what it came from??
the only thing that hasn't been replaced is the starter relay. Maybe that's the problem??
thanks
take care, be safe
tim
The starter relay is not part of the ignition circuit.
If the starter spins then leave it the way it is.
Crackedback
Well-Known Member
Throwing parts at IS NOT a solution or good approach.
Straight up hot wire it, battery to coil if even for a minute, does it start?
There have been multiple suggestion on what to do with testing circuits. Until you do that and have definitive answers as to where the voltage is disappearing, you will chase your tail.
JMO Carry on
Straight up hot wire it, battery to coil if even for a minute, does it start?
There have been multiple suggestion on what to do with testing circuits. Until you do that and have definitive answers as to where the voltage is disappearing, you will chase your tail.
JMO Carry on
pedal2themetal
Well-Known Member
HI,
I"m not throwing parts at it.. if you read all my post . the parts that have been put on it over the past year have all be put on by a several shops.. Not just me..
several ignition switches, a couple of ballasts, coil and key switch. all I was saying was the relay which I think is what adds the 12v to the coil has not been changed and maybe not..
I have been fighting this for a couple of YEARS.. two shops as well as myself.. I think it was YY1 that mentioned the grounding of the ICU ... and as I said one of the SHOPS added an extra ground to the ICU housing and when I looked at it last night the connection at the battery does not look good so I"m going to redo that today.. and go from there ...if it fixes it then I'm done.. I hope..
Every time someone works on it. It works for a little while and then starts acting up again in a short time.. this time it has only been a month since the last shop worked on it and its acting up again as of yesterday BUT today it has started each time and I haven't done anything to it?? Except I did wiggle that extra ground to the ICU housing so I''m fixing that..
thanks take care, be safe
tim
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