Mopar electronic conversion epic fail.

[Dsertdog]

Last month I purchased a Mopar electronic ignition conversion package from a very reputable seller. It is NOT a proform kit.

I installed it according to the very good instructions and the car wouldn't fire.|

It would fire right back up when I reinstalled the points distributor.

On a whim I bought a spare box, had both ECUs tested and bother were good. The seller did his level best to try and help me, but even he is stumped, saying it's some kind of weird wiring problem. Other than the ammeter bypass and a tach, the wiring is stock
.
I can offer all kinds of voltages and such, but I have tested everything for continuity and every wire checks out.

Here's what is strange. With the points distributor installed and the engine running, I have 10.1 volts between the coil positive terminal and ground.

When I plug in the ECU and the electronic distributor, the best I can get is about 7.5 volts at those terminals. Usually, it's about 6 volts. Not enough to run car.
I finally managed to start the car, but it ran poorly...rich and dank exhaust and it set the CO monitor off in the furnace room. Voltage at coil+ to ground was almost 8 then dropped. Car still ran but wouldn't restart after shut off.

Put the points distributor back in and she pops right off.

Help? Please?

1966 Polara 383

 

[MoPar~Man]

Maybe ECU has a bad ground connection. Did you check the timing with a timing light? See where it's firing?

 

[Fury1969WI]

you're changing the ballast resistor each time? It's been 30 years since i had my last points car (all converted to electronic) but i thought the ECU wanted a different resistance at the ballast.

Otherwise i'm with @MoPar~Man and suggest verifying timing. There could be mfr differences in those distributors, different advance curves, heavier spings.

 

[Dsertdog]

Maybe ECU has a bad ground connection. Did you check the timing with a timing light? See where it's firing?

Ecu is grounded with blind rivet nuts plus ground strapped to engine. Unpainted case also acts as ground.

Initial was set to factory spec.

 

[Dsertdog]

you're changing the ballast resistor each time? It's been 30 years since i had my last points car (all converted to electronic) but i thought the ECU wanted a different resistance at the ballast.

Otherwise i'm with @MoPar~Man and suggest verifying timing. There could be mfr differences in those distributors, different advance curves, heavier spings.

Ballast resistor is the same as points. Both test 1.7-1.8 Timing verified and advance has nothing to do with the voltage drop I'm experiencing

 

[Dsertdog]

halifaxhops

When I try to run the electronic system I have little or no fire at the secondary. I need at least 8.5 volts for coil+ to ground, and I have 5-6 volts with the key on.
With the points system I have 10.1 volts

 

[Gerald Morris]

Ballast resistor is the same as points. Both test 1.7-1.8 Timing verified and advance has nothing to do with the voltage drop I'm experiencing

Your POINTS ballast measures 1.7 ohms?! Or are you getting a voltage drop of 1.7 volts? I stick with a points ballast of .5 ohms, as specified for slab sided C body Mopars. At 1.7 ohms, your coil voltage WILL BE LESS THAN HALF THE TOTAL VOLTAGE AVAILABLE TO THE SYSTEM, AND WILL NOT FIRE THE PLUGS!

I suspect you have the wrong ballast resistance, though I admit that differing ECRs have their own requirements. I can believe a breaker point system will still fire with a high resistance ballast. Recheck your specs I say.

 

[CBODY67]

Considering how "dwell" affects timing, I find it hard to believe that changing the distributors does not affect your base timing. Unless you are re-timing the engine with each distributor swap.

I would check the voltage getting TO the ECU as there is a minimum voltage requirement for it to fire the plugs. THIS is important. Points have no such requirement, as long as there is enough juice to make a spark between the point contacts that can get to the spark plugs.

Please keep us posted.

CBODY67

 

[Dsertdog]

Your POINTS ballast measures 1.7 ohms?! Or are you getting a voltage drop of 1.7 volts? I stick with a points ballast of .5 ohms, as specified for slab sided C body Mopars. At 1.7 ohms, your coil voltage WILL BE LESS THAN HALF THE TOTAL VOLTAGE AVAILABLE TO THE SYSTEM, AND WILL NOT FIRE THE PLUGS!

I suspect you have the wrong ballast resistance, though I admit that differing ECRs have their own requirements. I can beleive a breaker point system will still fire with a high resistance ballast. Recheck your specs I say.

Yup and the guy that sold me the conversion package said either resistor will work.
Just so you know, I checked both resistors and the oem is 2.0 and the aftermarket is 1.9 I have a.o1 variance in the VOM so 1.9 and 1.8
My car runs great with the points and the stock resistor it's had for just over 60 years.

 

[Dsertdog]

Considering how "dwell" affects timing, I find it hard to believe that changing the distributors does not affect your base timing. Unless you are re-timing the engine with each distributor swap.

I would check the voltage getting TO the ECU as there is a minimum voltage requirement for it to fire the plugs. THIS is important. Points have no such requirement, as long as there is enough juice to make a spark between the point contacts that can get to the spark plugs.

Please keep us posted.

CBODY67

I check and reset the initial every time with a timing light.
That's the weird part Cbody67. With the engine off and the key on, I have 11.9 volts at the ecu plug. with the engine running I have 14.53. Now as you may surmise, I'm not running the electronic system, but that's the voltage.
Is there a minimum star voltage on the start side? That should be the brown wires.

 

[Gerald Morris]

Yup and the guy that sold me the conversion package said either resistor will work.
Just so you know, I checked both resistors and the oem is 2.0 and the aftermarket is 1.9 I have a.o1 variance in the VOM so 1.9 and 1.8
My car runs great with the points and the stock resistor it's had for just over 60 years.

OK, stick w the stock resistor, for now. I back-converted my '83 /6 D150 from Lean Burn to a conventional electronic ignition, using a "High RPM" brand ECR as the basis of the kit sold by my vendor. It works very well, now into its 4th yr of service with us. I THINK the impedance on the ballast R for this kit is 1.0 ohms, though I'll have to dig to be sure of that. JEGS also carries that line of ECR, FWTW....

Best of Luck in this. You might need to change out your starter relay, if **** remains funky for you. You MIGHT try a "hotwire" to your ECR, just to eliminate possible bullshit. Do that, bump your engine over, and see how it runs. If it runs well thus, you know your problem is in the old wiring. I've used such an approach to clear away confusion before, w good result.

 

[Dsertdog]

OK, stick w the stock resistor, for now. I back-converted my '83 /6 D150 from Lean Burn to a conventional electronic ignition, using a "High RPM" brand ECR as the basis of the kit sold by my vendor. It works very well, now into its 4th yr of service with us. I THINK the impedance on the ballast R for this kit is 1.0 ohms, though I'll have to dig to be sure of that. JEGS also carries that line of ECR, FWTW....

Best of Luck in this. You might need to change out your starter relay, if **** remains funky for you. You MIGHT try a "hotwire" to your ECR, just to eliminate possible bullshit. Do that, bump your engine over, and see how it runs. If it runs well thus, you know your problem is in the old wiring. I've used such an approach to clear away confusion before, w good result.

FYI. I'm using the "High RPM" kit as well. The starter relay is new and from the same vendor as the high rpm kit. The ballast is 1.8, that's what he sent.
Later cars used a 4 pole double ballast. I know you can convert lean burn but it's different than a 66
The vendor can't figure it out either. He's a long time Mopar guy.
At his request I ran a hotwire to the coil+ from battery+ and still couldn't start the car

 

[Gerald Morris]

FYI. I'm using the "High RPM" kit as well. The starter relay is new and from the same vendor as the high rpm kit. The ballast is 1.8, that's what he sent.
Later cars used a 4 pole double ballast. I know you can convert lean burn but it's different than a 66
The vendor can't figure it out either. He's a long time Mopar guy.
At his request I ran a hotwire to the coil+ from battery+ and still couldn't start the car

Damn! OK, you're making All The Right Moves thus far then. I leave you in his capable old hands bro, with the best wishes.

 

[Big_John]

Ballast resistor would only come into play after the car starts as it's bypassed for starting.

This is a bit of a shot in the dark, but easy enough to check. The resistance of the pickup coil in the distributor should be between 150 and 900 ohms. Basically check the resistance between the the two wires to the distributor. Also check the air gap of the reluctor to the coil pickup.

 

[Dsertdog]

Ballast resistor would only come into play after the car starts as it's bypassed for starting.

This is a bit of a shot in the dark, but easy enough to check. The resistance of the pickup coil in the distributor should be between 150 and 900 ohms. Basically check the resistance between the the two wires to the distributor. Also check the air gap of the reluctor to the coil pickup.

I checked that too at vendors request. It was around 220 or so ohms. He also had me tighten up the air gap to .006 That's when I got a weak secondary spark and the car started but ran like crap. It also wouldn't restart easily

Replaced the electronic distributor with the point unit and she popped right off.

 

[MoPar~Man]

Maybe the leads coming from the reluctor coil to the ECU are swapped? Have you pulled a spark plug and had a look at what sort of spark is happening while your cranking?

 

[73Coupe]

Why not stick with points. Ain't nothing wrong with points....