No spark

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AndygotaDart

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So I have a 318 with upgraded mopar electronic ignition. I've been testing no spark and I think it's the distributor pickup is bad. Could be the control module but I don't think so. I have no coil control. Car ran sluggish and I thought it was just tired. Anyway, my question is when I was checking power and grounds on the icm I noticed the plugs for ground to coil and the plug ground to distributor are wired backwards! Like I said it ran before, all be it not great.
It was just recently it quit and I got it to start twice before it died for good. No spark at all now.
No ballast resistor wired into system but I don't think it's needed with electronic system.
Coil has 12v but no control. Ohm numbers all good. Good coil I think.
Pickup has good ohm reading but only 120 mV AC when spun with key. A few sources on internet says should have about 200 mV
I replaced distributor cap and rotor cos the pintel was flattened down to nothing.
Tomorrow I'm going to rewire the entire ignition system to be sure it's proper.

Any ideas? I'm leaning to a bad pickup.
 
Is this the Mopar electronic ignition, or aftermarket?
If it's the Chrysler electronic ignition, you definitely DO need a ballast resistor. You may have cooked the ECU, they're not made for a sustained 12+ volts (only when starting, not in "run").
If it's not the Chrysler ignition, you need to tell us what brand it is. They all have their own requirements.
 
It's the Chrysler box. I figured it needed the ballast resistor hooked up, but many mopar guys more knowledgeable than myself say no need for one. Like I said I'm going to wire it myself the proper way.
We have owned and driven this car for a few years. No issues but like I said it ran jot great. Hard to start especially when cold(more choke issue)and when really hot.
 
Try disconnecting the dist. pickup. With the key in "run" and a test spark gap rigged to the coil tower, tap the exposed terminal of the engine bay side of the pickup connector to ground. One fat blue spark should happen each time

Measure coil V with key in "run." Coil + should be say, 6--10v (it varies) but not same as battery. NEG side of coil should be quite low, 1 or 2 volts. Quite high indicates coil is not conducting. Box must be grounded

Try jumpering 12V temporarily direct to coil +

Ballast resistor must be good. (Continuity)
 
The p/up generated voltage is dependant on dist speed [ rpm ] AND the air gap. Slow cranking due to a tired battery will reduce voltage.

Your p/up is working & NOT the problem.

The Mopar guys who say to omit the bal res are less knowledgeable, not more knowledgeable.....
The Chrys ECU requires a bal res to be used with the coil.
 
Be sure your ECU case is grounded well. If not you get a no spark situation.
 
Pics of everything sure would help. The more the better. This site has more knowledge in its little finger than all the other sites put together. Kim
 
Just so you know;
>Pick-ups are directional.
They will trigger the ECU spinning in either direction..... but when spinning in reverse the ECU gets confused and triggers the coil at random times and with random power. You can witness this randomness with a timing light, and reving the engine up just a little. The strobe will go nuts.
>4 pin ECUs will accept battery voltage full-time.
>5-pin ECUs require a dual-ballast, one each for the ECU and factory coil, and they are different.
>Non factory coils may or may not require a ballast, and may require a specific ballast, to run optimally..

From Wiki;
"The primary function of a ballast resistor in an ignition system is to regulate the voltage going to the ignition coil. During the start-up phase, the resistor allows a higher voltage to reach the coil for a strong spark."

It says "during the the Start-up phase", but this refers to start up of the ballast. This is NOT referring to starting the engine.
During this ballast start-up phase, the ballast is cold, and passes nearly all the battery voltage. As it warms up, the ballast will progressively reduce the supply voltage, ending somewhere near 3 to 5 volts lower than battery voltage, at the coil

If you run a coil that is designed to run ballasted, without a ballast, it will quickly begin to run hotter than it was designed for. Most coils are oil-filled, and the oil will carry the heat to the metal case, which will radiate it away. This will work for a while, but the coil will not endure this forever.
When the coil gets this hot, there is no predicting what the output looks like.
I have seen coils that leaked their oil away, not mine; but the result is a short life and failure.

Some old Chevy coils from the 60s and 70s;
were internally ballasted, and/or
some were ballasted inside the Run-wire.
These coils, IIRC, were always so marked;
"use with external resistor", or
"not for use with external resistor", or
some such nomenclature.
 
Thank you for all the info.
Its my wifes car and it ran decent albeit a little rough from day one. Lots of other issues but it started and ran with the current setup. Converted from points to electronic ignition. I cannot tell what ignition coil is in it as it has been painted completely black and there are no markings at all. I just assumed it was an internally resisted coil hence the ballast resistor not being hooked up and car started and ran ok. Its been like this for a couple years now. So it just quit(no start) one day on the road, got it running after banging on the carb and fuel pump, and swearing at the thing for an hour, but it backfired, missed and ran bad. I figured it was a carb issue all along. Now it has no spark at all. I tested continuity on all ignition wires(good). ICM box ground on firewall is good. Coil is getting 12V on + side when cranking, but no control on - side of coil. About 9V on + side and approx 1.4V on - side at run position. The distributor pickup seems to be working, there is continuity and a little over 1V AC cranking engine.
I am sure it is now a bad ICM. (Original Chrysler box)
The troubling part is the pin from the ICM that is supposed to go to coil - is actually wired to the distributer pickup. The pin on the ICM that supposed to go to pickup is wired to - coil. Seems wrong to me but it ran before so I assume it does not make a difference.
Either way I am redoing all the wiring and checking for breaks, dirt, corrosion. Switching to an externally resisted coil, wiring in a ballast resistor. and if still no spark I will replace the ICM.
My wife has spent a small fortune and has a built 360 with MSD ignition, new everything front to back, and its being put in it this winter so Im really just trying to get it running to enjoy it for a few months anyway.
 
Its running the mopar system right now. The new motor and all the other goodies will be installed this winter.
Now its a tired old 318 with the points converted to electronic.
 
AndygotaDart said:
Thank you for all the info.
Its my wifes car and it ran decent albeit a little rough from day one. Lots of other issues but it started and ran with the current setup. Converted from points to electronic ignition. I cannot tell what ignition coil is in it as it has been painted completely black and there are no markings at all. I just assumed it was an internally resisted coil hence the ballast resistor not being hooked up and car started and ran ok. Its been like this for a couple years now. So it just quit(no start) one day on the road, got it running after banging on the carb and fuel pump, and swearing at the thing for an hour, but it backfired, missed and ran bad. I figured it was a carb issue all along. Now it has no spark at all. I tested continuity on all ignition wires(good). ICM box ground on firewall is good. Coil is getting 12V on + side when cranking, but no control on - side of coil. About 9V on + side and approx 1.4V on - side at run position. The distributor pickup seems to be working, there is continuity and a little over 1V AC cranking engine.
I am sure it is now a bad ICM. (Original Chrysler box)
The troubling part is the pin from the ICM that is supposed to go to coil - is actually wired to the distributer pickup. The pin on the ICM that supposed to go to pickup is wired to - coil. Seems wrong to me but it ran before so I assume it does not make a difference.
Either way I am redoing all the wiring and checking for breaks, dirt, corrosion. Switching to an externally resisted coil, wiring in a ballast resistor. and if still no spark I will replace the ICM.
My wife has spent a small fortune and has a built 360 with MSD ignition, new everything front to back, and its being put in it this winter so Im really just trying to get it running to enjoy it for a few months anyway.
Click to expand...
Wow- it sounds like a total mess. OF COURSE the connections matter, regardless of whether it ran or not before. As you keep emphasizing, it ran like crap when it did run... it just sounds like the cobbled up wiring and components finally gave up the ghost.
You need to start over from square one with new components and stick to the proper wiring schematic, or it's never going to run right.
If you're using a five pin ECU (which requires a four pin ballast), use this diagram:
1724086117954.png

If you're using a four pin ECU (which only needs a two pin ballast), use this diagram:
1724086986278.png

Go over to MyMopar.com and download your factory service manual, which has all the wiring diagrams for your car. They're free.
Service Manuals – MyMopar
This way you'll be able to identify the necessary wires to splice into when you re-do that whole ignition wiring mess.
Better yet, go to Jeg's, Summit or Mancini and order the electronic ignition conversion kit; it will have all new components, a wiring harness that is a no-brainer to install, and complete instructions.
You can also download the conversion instructions from MyMopar.com:
https://www.mymopar.com/downloads/elecignconv.pdf
Even if you convert to the MSD at a later date (not sure why you would want to, but do what you want), you still need to get your wiring straightened out or you will just be making improper connections all over again and wondering why it still runs like sh*t after you dropped all that money into it...
 
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Oh it's a total mess alright. Like I said, it's been cobbled together front to back. I haven't wired anything myself. Just diagnosing and I took readings, compared them to those exact diagrams and I know this **** ain't right. I think you are right, it worked half assed until it gave up the ghost. I'm just surprised anything works when wired so badly.
For Pete's sake there's even tin foil wrapped around a glass fuse in the panel...I can't believe it didn't burn to the ground already. Lol
 
AndygotaDart said:
points converted to electronic.
Click to expand...
Should have just left it that way.

Anyway, the mopar electronic ignition system on these cars are simple in operation. Check the diagrams and you can see. My advice is to rip the current junk out and wire it up how Chrysler intended it to be with the correct wires going to the correct places and using the correct ballast resistor. Once you have that part of the ignition sorted, check the distributor pickup gap and see if you can get 200mv when it spins. Ohm check the plug wires, if you have close to 5000 ohms per foot they be junk. Heck, maybe 3000 ohms per foot may be the may be the max you should accept.

Since I don't feel like typing a wall of text, I'm just recommend this video by Scanner Danner.
 
Update...

Got the ignition wiring sorted and a ballast resistor installed. Adjusted the pickup coil air gap. It was out by a few thousands. Got the coil to spark but it still would not start. It tried desperately to fire but couldn't. I tested the spark from the coil with a gap tool and found the coil spark was weak. So I put in a new coil, it fired right up. Two separate issues. The coil ohm test was within spec albeit secondary winding was at low limit. An experienced mechanic probably would of checked that reluctor gap sooner but it's running and my wife is happy.

Happy wife=happy life.
 
AndygotaDart said:
It's the Chrysler box. I figured it needed the ballast resistor hooked up, but many mopar guys more knowledgeable than myself say no need for one. Like I said I'm going to wire it myself the proper way.
We have owned and driven this car for a few years. No issues but like I said it ran jot great. Hard to start especially when cold(more choke issue)and when really hot.
Click to expand...
They aren't knowledgeable. It must have the ballast in line or you will burn the ignition box and or coil out. Find some new friends.
 
AndygotaDart said:
Update...

Got the ignition wiring sorted and a ballast resistor installed. Adjusted the pickup coil air gap. It was out by a few thousands. Got the coil to spark but it still would not start. It tried desperately to fire but couldn't. I tested the spark from the coil with a gap tool and found the coil spark was weak. So I put in a new coil, it fired right up. Two separate issues. The coil ohm test was within spec albeit secondary winding was at low limit. An experienced mechanic probably would of checked that reluctor gap sooner but it's running and my wife is happy.

Happy wife=happy life.
Click to expand...
Glad you got it!
 
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