Are you ready for a real weird one? Random NO spark from a MP electronic ignition system despite numerous parts swapped around...

[Cheapsunglasses]

ABSOLUTELY TRUE......electronic ignition systems are not to be trusted......
BOB RENTON

Really, you’re going to play that bullshit game again? ANY SYSTEM CAN FAIL!!!!!!!!!!! Don’t be a clown and talk trash at someone’s misfortunes!!!!


@Kern Dog , I know it’s a silly question, but have you wiggled and made sure every connector and ground is tight?

Or here’s a possibly, and I might be waaay off in left field. Maybe a solder came loose somewhere and maybe the heat and a random vibration just happens to cause the problem?

Unlike some clowns here, I wish you the best of luck, your car is beautiful and you’ve put so much work into it, it really sucks this happens.

 

[Cop car wagon]

I have had 2 separate experiances wirh cranking speed not fast enought to activate the pickup. They wouldn't crank start, but they would bump start.
ECU passed the distributor connector scratch to ground test each time. (Coil output)
Bench testing the distributor proved that you could spin the shaft and not get a signal until you spun it faster.

 

[MWbirdLOVER70]

Just when you think that you have a situation solved….

View attachment 1701117

I have to state that at least when you have a shiny car on a trailer, people think you’re going to a car show.

View attachment 1701119

Months have gone by with not one instance of no-spark.
Today I had her out and after rapping it up to 6000 in 1st gear, it started to stumble then shut down. I thought I was out of gas but the accelerator pump shot was strong.
It cranked fast but almost in an instant, slowed way down.
The wife came out, I went back for tools and parts.
Nothing helped. At times it acted like it wanted to start as I released the key. This symptom occurs with other cars I’ve had and I’ve yet to determine what causes it. No, it isn’t the ignition switch. I’ve tried a spare numerous times. The battery was down to 12.1 volts so I used the Hulkman charge box. It still cranked slow as if the extra reserve power meant nothing.
I’ll report more as I get deeper into it.

Starter shorting out in windings when hot? Coil windings? Throwing spaghetti here KD

Did you blow it up at 6000 RPMs

First thing your going to do is have someone crank it over in the start position while you put a volt meter on the positive side of coil , you should have full battery voltage

If you do not have full battery voltage , then the volt meter goes back to the ballast resistor looking for full battery voltage , then back to your bulkhead connection , then to ignition switch

If it is trying to start as you release the key back to the run position , you are getting voltage only in the run position

But I am sure you have been told that a million times

Believe it or not I had a ballast recently do that but on crank was hit or miss. Sure enough she was bad but borderline. Changed from my stash and bingo but I’m sure you’ve checked that

 

[MWbirdLOVER70]

Really, you’re going to play that bullshit game again? ANY SYSTEM CAN FAIL!!!!!!!!!!! Don’t be a clown and talk trash at someone’s misfortunes!!!!


@Kern Dog , I know it’s a silly question, but have you wiggled and made sure every connector and ground is tight?

Or here’s a possibly, and I might be waaay off in left field. Maybe a solder came loose somewhere and maybe the heat and a random vibration just happens to cause the problem?

Unlike some clowns here, I wish you the best of luck, your car is beautiful and you’ve put so much work into it, it really sucks this happens.

Second on double checking connections, crimps and solder joints and grounds even on the ECM box. Sorry for to many posts, just trying to help brother

 

[Kern Dog]

Let me state this first off...
I appreciate all responses that offer help. Many of the problems we deal with are within my skill level but no spark issues just kick my ***. I get pissed and my diagnostic skills get worse when I'm mad.

, I know it’s a silly question, but have you wiggled and made sure every connector and ground is tight?

Or here’s a possibly, and I might be waaay off in left field. Maybe a solder came loose somewhere and maybe the heat and a random vibration just happens to cause the problem?

Wiggling wires is one of my first things to try. I've never thought to have someone else crank the engine while I am wiggling them though.

I have had 2 separate experiences with cranking speed not fast enough to activate the pickup. They wouldn't crank start, but they would bump start.
ECU passed the distributor connector scratch to ground test each time. (Coil output)
Bench testing the distributor proved that you could spin the shaft and not get a signal until you spun it faster.

This is possible. I have tested distributor operation by spinning the distributor shaft with an distributor that is out of the engine so even at hand speed, I've had them work.

Second on double checking connections, crimps and solder joints and grounds even on the ECM box. Sorry for too many posts, just trying to help brother

I do appreciate the effort. You never know what the other guy is thinking or what he has tried. Sometimes the simple things get forgotten or overlooked.
To recap, I got in the car yesterday and went for a short drive. It was about 90 degrees here and the car was up to temperature reasonably quick. I leaned on the throttle a bit, not too much though. At one point, I made a U-turn when another car was coming up a little faster than I thought, so I got on the throttle pretty good and shifted to second, when the car started slowing. I thought I was out of gas since getting gas was on the list of things to do. The tach dropped to zero and despite cranking, the car wouldn't restart. I coasted to a shady spot and started diagnosing.
My first thing was to check the carburetor for fuel and it had a strong stream from the accelerator pump. I checked all underhood connections and they were fine. I tried a different ballast resistor and then the engine started cranking slow. It started fine at home but the car has been sitting for a couple months so maybe the battery was already discharged a bit and the extended cranking later may have drained too much reserve.
I am always amazed at the scale of charge that is commonly posted:

I always have a hard time wrapping my head around how a 12 volt battery can be at 50% charge when it reads barely over 12 volts. I was under 12 at one point so I used my Hulkman jumper:

It acted like it wasn't even connected. The engine didn't spin any faster. In fact, this has happened a couple of times with this unit where connecting it made either a HUGE difference or none at all. Maybe the clamps didn't have a good connection?
I trailered the car home and charged the battery, then tried cranking it again. Still nothing. I'll get back to it in about an hour and have an update when things develop. Thanks again.

 

[NoCar2023]

"I tried a different ballast resistor"

I thought you installed the FBO ignition module.

 

[Fran Blacker]

Probably said already 10 times have you felt the positive cable from battery to see it is hot. Check from battery to as close to starter as you can get. Laser temp reader on cable and other ignition /starter wires.

 

[RJRENTON]

Let me state this first off...
I appreciate all responses that offer help. Many of the problems we deal with are within my skill level but no spark issues just kick my ***. I get pissed and my diagnostic skills get worse when I'm mad.


Wiggling wires is one of my first things to try. I've never thought to have someone else crank the engine while I am wiggling them though.



This is possible. I have tested distributor operation by spinning the distributor shaft with an distributor that is out of the engine so even at hand speed, I've had them work.



I do appreciate the effort. You never know what the other guy is thinking or what he has tried. Sometimes the simple things get forgotten or overlooked.
To recap, I got in the car yesterday and went for a short drive. It was about 90 degrees here and the car was up to temperature reasonably quick. I leaned on the throttle a bit, not too much though. At one point, I made a U-turn when another car was coming up a little faster than I thought, so I got on the throttle pretty good and shifted to second, when the car started slowing. I thought I was out of gas since getting gas was on the list of things to do. The tach dropped to zero and despite cranking, the car wouldn't restart. I coasted to a shady spot and started diagnosing.
My first thing was to check the carburetor for fuel and it had a strong stream from the accelerator pump. I checked all underhood connections and they were fine. I tried a different ballast resistor and then the engine started cranking slow. It started fine at home but the car has been sitting for a couple months so maybe the battery was already discharged a bit and the extended cranking later may have drained too much reserve.
I am always amazed at the scale of charge that is commonly posted:

View attachment 1701389

I always have a hard time wrapping my head around how a 12 volt battery can be at 50% charge when it reads barely over 12 volts. I was under 12 at one point so I used my Hulkman jumper:

View attachment 1701390

It acted like it wasn't even connected. The engine didn't spin any faster. In fact, this has happened a couple of times with this unit where connecting it made either a HUGE difference or none at all. Maybe the clamps didn't have a good connection?
I trailered the car home and charged the battery, then tried cranking it again. Still nothing. I'll get back to it in about an hour and have an update when things develop. Thanks again.

The best way to determine the battery's state of charge is to check the specific gravity of the electrolyte, corrected for temperature. A fully charged battery will have a specific gravity of 1.265-1.270, measured with a hydrometer. The number go down as the battery discharged. The second best method to test the battery's state of charge is by doing a LOAD TEST AND WHILE UNDER LOAD, MEASURE THE TERMINAL VOLTAGE TO NOT BE LESS THAN 10.0-10.5 volts. Measuring terminal voltage without a imposed load means nothing. A battery is a chemical store house.....lead (Pb) and lead dioxide (PbO2) plus sulfuric acid (H2SO4) and water as the electrolyte. A battery does not store amps contrary to popular belief. The charge/discharge cycle is complex. If it, the battery, cannot produce the required chemical reaction to generate the starting energy, it is SULFATED and should be replaced. Just my opinion of course......
BOB RENTON

 

[68 Sport Satellite]

KD - this happened to me twice before in similar conditions - hot outside, had driven car for a few miles before decreased power, shutdown, and won't restart. Both times after letting car sit for 30 min, it started. Both times it turned out to be the oil filled coil had got too hot. I switched to an epoxy filled coil and all has been well ever since. I hope you figure it out.

 

[Kern Dog]

"I tried a different ballast resistor"

I thought you installed the FBO ignition module.

I have the FBO advance limiter plate but that is all I have from them.

Probably said already 10 times have you felt the positive cable from battery to see it is hot. Check from battery to as close to starter as you can get. Laser temp reader on cable and other ignition /starter wires.

I did not feel the battery cable. The battery is in the trunk and the main cable from the starter to the trunk mounted solenoid is only live when I am cranking it over. At the starter end, it is clear of the headers.

Again, thank you to all that took the time to chime in. The car is back up and running and what went wrong is a bit disappointing to me.
Two parts failed at the same time though I don’t know how or why. Both the ballast resistor and ECM crapped out. I had some help today….

Rich, AKA CoronetDarter came over in the Coronet. He brought tools and was a welcome help. He has a form of electronic ignition so we used the Coronet as a test mule along with two other cars here and a truck. We tested voltage at the coil and ballast on the Coronet, my 72 Duster:

A 75 Power Wagon:

Of course, Jigsaw…

Every vehicle had a different number. The Coronet and “Ginger” the red car had the highest readings, near 11 volts with the engines off. The other cars varied between 7-9 volts yet they all run fine. Checking the other cars was intended to reveal a weakness in the red car since it wouldn’t start. Instead it confused me because that low of a voltage reading should not start and run.
Yesterday on the roadside, the car was untouched and not starting so my diagnostic list was 1) Check for fuel, 2) Wiggle wires looking for loose connections 3)Replace ballast resistor. Each thing I did was followed by trying to start it.
At home I figured the ballast resistor was fine since changing it made no difference so I put it back in. I charged the battery. This morning I put in a different ECM and still no spark. Rich noticed that the plastic connector to the ballast didn’t click on with a snug fit. He thought maybe it could be partially to blame. The terminals on the BR wiggled a little, I don’t know if that matters. I think It is a ballast that came with an MSD coil, I don’t recall. All the times I’ve had random no spark issues, I’ve swapped around parts. I don’t remember where all the stuff came from.
I replaced the ballast resistor with a spare from the shed and BOOM, it starts and runs!

That is a generic parts store ECM that is supposedly rated to about 5000 rpms. It is fine for now. At this point, I knew the ballast resistor was bad but To confirm things, I tried the blue ECM I was using along with an MP Chrome box.

I tried the blue and chrome boxes in the Duster and neither one worked in that car either.
Yes, I threw them out. I have made the mistake of putting junk electronic parts back in the shed only to be pissed later when they don’t work.

 

[Cheapsunglasses]

First of all congratulations! Secondly coronetdarter has a beautiful car!

 

[Kern Dog]

I keep a spare ballast resistor and ECM in the trunk but never expected to have both fail at the same time like it did here.
I don’t know how that happens but my bonehead diagnostic skills are working on that.
The car has been sitting several weeks but did start and run fine yesterday. I did not look at the voltmeter but when the engine is running around 2000 rpms with no A/C on, it is charging just under 14 volts. I’m assuming the battery charge may have been low but still enough to start and run. Out on the drive, I ran it up to approximately 6000 rpms and it stalled not long after. What if the rpms spiked alternator output (since it was recharging a partially discharged battery) and the spike killed the ignition?
Is that even likely or possible? I’m grasping at straws here.
During today’s efforts, I would sometimes get that weird action where it seemed to try to start just as I released the key. This is often a ballast resistor issue that some people blame on the ignition switch. I have several ignition switches here and even though I never have had it make a difference, when I’m desperate, I do try another switch. I have had such a weird and conflicting set of symptoms at times, the long shots and desperate ideas are still tempting to try.
Here is one:
Years ago I had this same thing. After swapping one part at a time with no improvement, I sprayed ether down the carb and cranked it up and it ran. It had fuel, there was no spark at the #1 plug wire but somehow, starting fluid triggered something and it was fine. Other times I’ve tried the starting fluid and it made no difference. This random set of symptoms and failures makes diagnosis very difficult.
What is disappointing is that two parts failed at the same time, they were fairly new and not Harbor Freight level parts.
Also disappointing is that I had these parts in the trunk. I could have swapped both of them and driven home.
What is great is that the problem and the fix were handled with no serious problems and no cost. I will look for a higher performance ECM though.
During the troubleshooting, I did look at the bulkhead wiring and it was fine.

 

[CoronetDarter]

The other revelation was when I was pulling the leads off the BR. The coil side connector gave resistance when pulling it off, the ignition side connector practically fell into my hand by barely touching it. Swapping BR's gave a tighter resistance on the spade terminals, and Greg crimped down the female connector on the offending wire.

 

[NoCar2023]

I'm glad to hear you got it running. What do you think is the cause of these failed components?

BTW, This solved my intermittent spark issues. I also wired in an IGN relay.

 

[Kern Dog]

Having Rich there to bounce ideas back and forth was great.
I really like having a friend around to tinker on cars. We spent about the same amount of time jabbering as we did working but I had a good time.
Thanks Rich.

 

[Kern Dog]

I'm glad to hear you got it running. What do you think is the cause of these failed components?

BTW, This solved my intermittent spark issues. I also wired in an IGN relay.

View attachment 1701601

It is a mystery to me as to why the parts conked out. It ran fine until I romped on it. I have never heard of breaking an ignition from revving too high…. Pistons and valves, sure but a spark box? A ballast resistor?
I’d love to know why they failed so I can avoid future issues.
I did try one of those FBO ignition boxes but it made my tachometer bounce a lot. I tried putting a diode in the line to the tach wire but it didn’t help so I went back to a regular Mopar style ECM.

 

[CoronetDarter]

Having Rich there to bounce ideas back and forth was great.
I really like having a friend around to tinker on cars. We spent about the same amount of time jabbering as we did working but I had a good time.
Thanks Rich.

For sure. We spent 4 hours to troubleshoot for 1/2 hour. Although part of the time was making a strawberry run to the local produce stand.

 

[Kern Dog]

For sure. We spent 4 hours to troubleshoot for 1/2 hour. Although part of the time was making a strawberry run to the local produce stand.

Yeah....
Get this: We took the Coronet out to get strawberries for my wife...who plans to make ice cream later.
You cannot go out in a nice looking classic car and blend in. These cars stand out and bring attention. Some guy came up to Rich to chat about the car. Just as it was his turn to get his own strawberries, I pulled him out of line to stand behind the car. I wanted to show him why many of us LOVE these cars...It was the bulging hips! The Dodges have great hips like a woman does!

The man agreed. He had to get out of line to see the car but I don't think he minded. He still got his strawberries.

 

[Cheapsunglasses]

yep, I drive my car pretty regularly, no matter where or how often, every time I see my car in the crowd of boring refrigerators it makes me chuckle.

This is exactly what these cars are about, grabbing a buddy or sometimes more, hanging out, maybe something gets fixed (thankfully this time it did,) maybe not, buts it’s always a good time!

 

[CoronetDarter]

Yeah....
Get this: We took the Coronet out to get strawberries for my wife...who plans to make ice cream later.
You cannot go out in a nice looking classic car and blend in. These cars stand out and bring attention. Some guy came up to Rich to chat about the car. Just as it was his turn to get his own strawberries, I pulled him out of line to stand behind the car. I wanted to show him why many of us LOVE these cars...It was the bulging hips! The Dodges have great hips like a woman does!

View attachment 1701640

View attachment 1701642


The man agreed. He had to get out of line to see the car but I don't think he minded. He still got his strawberries.

I gave him bonus points because he knew it was a Dodge (or maybe he just read the DODGE on the trunk panel). He lost his place in line, but it was worth it.