Electronic ign, no spark.

Carmine

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Just bought another C. (To be revealed at a later date.) Prior owner paid someone to install a typical Chrysler electronic ignition kit to replace a LB system. On my way to look at it (it was about 50 miles away) the owner called and said it suddenly wouldn't start.

As I suspected, the install is terrible. Putting aside the sloppy zip ties and randomly colored wires, the biggest fault I found was the black/yellow - coil wire connected to +. (This wire comes directly out of the control module harness and turns the coil on/off to induce the high voltage.) Experience tells me a coil will work backwards, but with reduced efficiency.

I corrected this and verified the + side was connected to the ballast resistor.

That only leaves the wires that receive the on/off signal from the distributor pick up. These were correct, and a verified the wiring was good by doing the ohmmeter test at both the module connector and the pick-up. It read about 250 ohms, which is well within spec. (190-900 ohms)

So I swapped the ignition module from my RMB. Still no spark. For the hellavit, I put the "suspect" module in my RMB... No spark. Hmmm.

Now I checked the coil by substitution. No spark.

At this point, I've verified the wiring (including the ballast) and substituted both the module and ignition coil. I have correct voltages at terminal ends. I have a reasonable resistance across the pick-up coil. There is not much left... beyond a substitution check of the pick-up coil.

As a last gasp before the rain and wind drove me inside, I just connected the coil straight to battery positive (basically hot wiring the car). I still had the coil wire positioned to check spark, and I got a nice hot one every time I connected and disconnected said hot wire.

Who wants to take a stab at this? I'll be back at it tomorrow.
 

Davea Lux

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Just bought another C. (To be revealed at a later date.) Prior owner paid someone to install a typical Chrysler electronic ignition kit to replace a LB system. On my way to look at it (it was about 50 miles away) the owner called and said it suddenly wouldn't start.

As I suspected, the install is terrible. Putting aside the sloppy zip ties and randomly colored wires, the biggest fault I found was the black/yellow - coil wire connected to +. (This wire comes directly out of the control module harness and turns the coil on/off to induce the high voltage.) Experience tells me a coil will work backwards, but with reduced efficiency.

I corrected this and verified the + side was connected to the ballast resistor.

That only leaves the wires that receive the on/off signal from the distributor pick up. These were correct, and a verified the wiring was good by doing the ohmmeter test at both the module connector and the pick-up. It read about 250 ohms, which is well within spec. (190-900 ohms)

So I swapped the ignition module from my RMB. Still no spark. For the hellavit, I put the "suspect" module in my RMB... No spark. Hmmm.

Now I checked the coil by substitution. No spark.

At this point, I've verified the wiring (including the ballast) and substituted both the module and ignition coil. I have correct voltages at terminal ends. I have a reasonable resistance across the pick-up coil. There is not much left... beyond a substitution check of the pick-up coil.

As a last gasp before the rain and wind drove me inside, I just connected the coil straight to battery positive (basically hot wiring the car). I still had the coil wire positioned to check spark, and I got a nice hot one every time I connected and disconnected said hot wire.

Who wants to take a stab at this? I'll be back at it tomorrow.

I would check the free air gap on the distributor pick up unit. They can be really picky. The resistance test of the pickup unit has determined that the unit is probably not shorted, but that does not necessarily mean that it is still working. Try changing the pickup unit and be sure to verify that the ECM is properly grounded.

Dave
 

Carmine

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Does the distributor turn?...broken/loose timing chain??????

Valid suggestion! I did leave the ohmmeter connected to the pick-up coil and the reading changed during cranking, so I must assume the reluctor on the distributor shaft turns. Cranking also sounds very normal/healthy.
 

Carmine

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FWIW, I would tend to believe the previous owner that the car had been running recently. This is no barn-find.
 

70NEWYORKER

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Check all grounds: ECU and Distributor body
OHM out coil primary and secondary windings
Ohm out coil to dist secondary wire
OHM out primary positive wires back to battery positive terminal(key needs to be in run position) ...might be high resistance,enough power to light a test light but not enough to run the ignition system.
 

Dobalovr

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FWIW, I would tend to believe the previous owner that the car had been running recently. This is no barn-find.

That rules out timing chsin and dizzy shaft which was my suggestion as I spent a day chasing the same problem only to find the new outta the box proform dizzy shaft was 3mm shorter and not engaging the drivegear on the cam. Replaced all the same components you have only to put a used dizzy back in place of the “new one “
 

Davea Lux

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If the noise suppression condenser is is still attached to the coil, you can also try removing it as they will sometimes short out and cause a big voltage drop to the coil.

Dave
 

Wollfen

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Check the positive side of the coil with the ignition on and see what voltage you have, I am having basically the same problems with mine and I found I only had 6 volts, I'm guessing it's something in the wiring harness itself or as already mentioned a ground problem.
 

Carmine

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If the noise suppression condenser is is still attached to the coil, you can also try removing it as they will sometimes short out and cause a big voltage drop to the coil.

Dave

I disconnected it as soon as I began troubleshooting, but good thought.
 

Carmine

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I do. Good idea.

I believe I've found the ultimate problem. That spin-the-spare technique was a great help. Let's say it all boils down to a stack-up of issues involving the poor installation of what was likely a Chinese knock-off MP kit. Worthy of its own thread with pics.
 

Turboomni

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Let's say it all boils down to a stack-up of issues involving the poor installation of what was likely a Chinese knock-off MP kit. Worthy of its own thread with pics.

I thought all the MP electronic ignition kits have been made in China for quite awhile now. Some guys with the MP kit say it's a good idea to carry a spare. It would be worthy of another thread. Maybe they have gotten better,who knows? [I doubt it though]
Glad you found the problem.
 

halifaxhops

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prob the pick up coil the get hot and open sometimes forever. $20 fix.
 

Mid70's Chrysler Fanatic

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I gotta follow this thread because I'm having similar problems with my '74 T&C. Of course it would die on a highway, miles from home, rather than in my driveway - and right between my house payment and Payday. At least the mechanics at work (actual mechanics, unlike the armchair one described below) were able to do a roadside diagnosis and identity the ignition pickup module (not the coil or wires) as the likely culprit. The quote below from yourmechanic.com looks like I wrote it myself; it's that dead on.

"One of the first symptoms of a bad ignition pickup is an engine that stalls. An old or failing ignition pickup may cut out signal intermittently, which may cause the engine to stall. The engine may suddenly just shut off, almost as if the key had been turned off. Depending on the nature of the issue, sometimes the vehicle can be restarted and driven again after a brief period of time. However, this problem will persist and worsen until it is taken care of."
If the above (and my thread on allpar.com) are wrong, FCBO and this thread will help me find the problem.

A coworker insists (based on prior experience with her KIA Spectra, I assume) that I can bypass the distributor by connecting jumper cables to the alternator.

I like the response I got on Allpar.com: "Yeah, definitely an off the wall response from your co-worker. If the Hall effect is in fact bad, you can't jump it for anything. Replace it."
 
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