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Mopar electronic ignition ECMs: Which to consider and what to avoid!

Hate to say this walk away for a few then use the troubleshooter in the FSM makes it alot easier and you wont miss anything.
 
I hate to think that to keep these cars running, I have to keep spare parts like this nearby and be ready to swap out the junk when it conks out.
I want vacuum advance so that leaves out some of the MSD and other options.
If I knew a points distributor would be reliable, I'd just go back to that. Maybe it is, I just don't know.
THIS car:

Dart blue 1.jpg


I assembled and got running in 2005 using a points distributor in a rebuilt 360. I don't know how many miles I have on it but I've bashed and thrashed around with this car for 19 years and never had an ignition problem. I've never reset or replaced the points in it.

********************************************************************************************************************
Let's say in theory, I wanted to try a points distributor in the car yet retain the firewall mounted electronic ignition stuff to save from having to block off the mounting holes.... Is it as simple as just attaching the wire from the distributor to the negative side of the coil? Will the car run wired that way with the electronic system not connected to the distributor and just along for the ride?
 
The first thing that comes to mind- is that actually grounded good?
Looks like a lot of bracketry, and the ground is on top of the paint.

I was never able to afford the DC/MP kit, so all my conversions were done with junkyard parts and home splicing.
Most every ECU failure I've had was preceded by goo leakage.

I carry a spare brain, ballast, and an alligator clip 14 or 16 gauge 3-4 foot jumper in my trunk.
 
Guys still race with points. Think the maintenance on a points system isn't much consider the bs going on. You'd change points once a year or two depends on miles driven. Did you have any alternator/voltage regulator problems lately?
 
Basic issue today is the price-oriented supply chain have cheapened up, lowering the quality level and end reliability of crucial ignition parts.
The older Mopar OE parts tend to last much longer than some of the later out-sourced parts.
Fortunately for me I still have a private stash..
Sad situation but reality...

Just my $0.02... :thumbsup:
 
Guys still race with points. Think the maintenance on a points system isn't much consider the bs going on. You'd change points once a year or two depends on miles driven. Did you have any alternator/voltage regulator problems lately?

Regular replacement of wearing parts doesn’t bother me. Immediate replacement when a new part fails with zero warning pisses me off.
I have not had any charging issues, though I would like to upgrade the charging system with an alternator that charges better at idle.
 
Accel 8140 - 1.5 Ohms

Accel 8145 - 0.7 Ohms

Both yellow , both canister

Anyways try to find a quality ballast resistor , talk to Hops in the 0.5 - 0.8 Ohm Range



Looking at the picture of your ECU / Ignition Module you just installed , looks like an older Wells maybe , but it has a real Transistor mounted - Might actually bee decent



Take it out on the street and wrap it up to 10,000 RPMs , you will know real fast what is working

LOL
 
An stablish charging system will help A LOT on the life durability of any Ign System. A poor charging system will be constantly changing the voltage rates “trying” to keep up the power required around.
 
There are times when you think that a problem is behind you… that whatever was causing the trouble is corrected.
Today I went to move the car and got the same no spark issue again.
Now this is where having diagnostic skills can get you running again.
As stated, I’ve had the habit of just changing parts until it runs when dealing with having no spark. To me, that is a poor method to live by. I want to be able to pinpoint the problem and concentrate on it instead of shooting a bunch of parts at it.
I tested resistance at the coil and it was the same 1.5 number as before. The ballast resistor was between .08 and .09. I used a simple jumper wire between the harness terminals for the ballast resistor.

1C549C94-B8F6-461D-A90C-A695B4F6374B.jpeg


It started up fine. Then I reconnected the terminals to the ballast resistor again and the car started.
One would think that I had a bad connection before. Maybe I did. I did wiggle the wires and try to start it with no luck.
Bonehead logic moment:
If a problem exists over a period of time where numerous parts fail, maybe what is causing the failures is not just the parts themselves but the parts that have not been replaced.
I know, I’m reaching here but what if these wires and terminals are not crimped right or secured?

40761E70-1B0E-4CD3-BF3A-DEFE695A83E8.jpeg


The right side was a loose fit on the other ballast resistor. It fits this one okay.
Can a bad connection lead to total failure of a ballast or ECM?
Here is another one…if a ballast resistor shows adequate resistance, can it still cause a no spark?
 
That’s why I mentioned days ago to get your volt meter out and go from here to there to here to there

Anyways see those black plastic covers over the wire terminal ends

You should see a metal tab or tang on the actual wire terminal inside the cover , try to get a tiny screwdriver next to the tab and remove those plastic covers

Let’s look at your wire terminals ends and see if you have a bad connection or crimp
 
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A poor crimp or connection caused this resistance over the years on this positive coil wire on a brand new reproduction harness

Car ran 99% of the time , but the RPM issue and occasional misfire

Problem was you couldn’t see it until the insulation and rubber was removed


Drove me nuts

Had the same issue on a reproduction positive battery cable for a 71 B Body

IMG_0331.jpeg
 
Wire to terminal connections are always a bugger to diagnose when they are enclosed in those plastic shrouds. In the past 10 years I have had 3 bad connections on brand new M&H harness', so it definitely happens.
 
This is an Evans harness. I won’t blame him though. I’ve had this no spark issue before I got this new harness. I’ve driven the car more since and had more failures so it is hard to determine. I’ll get a look at it and take some pictures.
 
Hate to say this walk away for a few then use the troubleshooter in the FSM makes it alot easier and you wont miss anything.
But sometimes (most of the time) the perspective person is searching for a quick horse power increase and an electronic ignition system seems to be the "easiest" way to get what is desired.....but the person is usually disappointed or has functionality problems....won't start, runs poorly or breaks down stranding the owner. Perhaps the old Confucius saying is applicable: "Fancy gizmos don't work and if they do work, they stop working at the MOST inopportune time"........but ....you pay your money and take your choice....there are some excellent in-depth articles on the FABO site regarding this subject even to the replacement of external switching transistor, with a power Darlington type in a TO3 case, capable of the high current switching and/or no ballast resistor for those people that insist on mix matching components.....because "my buddy" did so without any problems.....(that he's willing to disclose). The fix? ......carry some spare parts...ECU, ballast resistor, coil, etc....btw....this is the 358th iteration of this subject to date......
BOB RENTON .
 
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BOB - I carry a spare 383 Magnum in my trunk , just incase , you never know when
 
One to avoid!!!!!!!!!!!!
Absolute Chinese garbage!
I would stick with points before buying this trash again.
1722385470708.png
 
There are times when you think that a problem is behind you… that whatever was causing the trouble is corrected.
Today I went to move the car and got the same no spark issue again.
Now this is where having diagnostic skills can get you running again.
As stated, I’ve had the habit of just changing parts until it runs when dealing with having no spark. To me, that is a poor method to live by. I want to be able to pinpoint the problem and concentrate on it instead of shooting a bunch of parts at it.
I tested resistance at the coil and it was the same 1.5 number as before. The ballast resistor was between .08 and .09. I used a simple jumper wire between the harness terminals for the ballast resistor.

View attachment 1702661

It started up fine. Then I reconnected the terminals to the ballast resistor again and the car started.
One would think that I had a bad connection before. Maybe I did. I did wiggle the wires and try to start it with no luck.
Bonehead logic moment:
If a problem exists over a period of time where numerous parts fail, maybe what is causing the failures is not just the parts themselves but the parts that have not been replaced.
I know, I’m reaching here but what if these wires and terminals are not crimped right or secured?

View attachment 1702662

The right side was a loose fit on the other ballast resistor. It fits this one okay.
1. Can a bad connection lead to total failure of a ballast or ECM?
2. Here is another one…if a ballast resistor shows adequate resistance, can it still cause a no spark?
1. Of course - a break in a circuit is a break in a circuit, which is what a bad/intermittent connection is.
2. Sure, if there's a problem with the connections. :)
(Ballasts will, in rare occasions, sometimes fail when hot, but work when cold too).
 
1. Of course - a break in a circuit is a break in a circuit, which is what a bad/intermittent connection is.
2. Sure, if there's a problem with the connections. :)
(Ballasts will, in rare occasions, sometimes fail when hot, but work when cold too).
It has been my experience that the ballast resistors that are sealed with a ceramic compound and have DALE (the manufacturer) printed on them, run very hot and are prone to failure. The open back ballast resistor units, where the element is visible run cooler, like the OEM units and are extremely reliable. The open ballast resistor on the GTX had been there for 30+ years ......but still carry a spare......
BOB RENTON
 
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