MP elctronic conversion ecm question

[Ghoste]

I know the orange boxes are notorious for frying in these things, but my question is can they fail intermittently?
My limited understanding of electronics tells me that solid state either works or it doesn't but I am beginning to wonder if it's possible that I have an ecm that is failing only some of the time.  Is this possible?

[Plumcrazy]

You can have an intermittent problem with any electronic device on a car.
Electronics don't like heat or vibration, you have both in an automobile.

[beenaround]

i,ve replaced 3 orange boxes  in the wifes 78 cordoba,2 in my friends challenger.all inside of 2 years i finally moved the box outward to the right inner fender on the cordoba.so far so good.i also ran a heavey duty ground strap to the box.now for comparison my 70 rt has been using the same orange box for 25+ years.my thoughts?cheap out sourcing of parts.i think the problem is with the transister they use.somehow it can't take any kind of eletrical shock.the coding on the transister shows that it is made in a foriegn country.and the best part is that mopar performance parts have no warranty.

[Ghoste]

Beenaround, did they fail intermittently or just go dead and that was it?

[8WHEELER]

Most of the time they just go bad, there are times where they will work but not well putting out low volts and not producing enough spark to run well. But its electrical so it can be intermittent.

Dan

[Ghoste]

Intermittent as in a no start condition and then after sitting for a while, they miraculously start?

[8WHEELER]

Yes that can happen easy, car is hot then cools down then works for awhile...

Dan

[Ghoste]

What if it's not hot?

[beenaround]

oh it can do that also.we took the one from the wifes cordoba,put it in the challenger and it worked for 5 minutes then died!!!it gets fustrating!!!

[Ghoste]

Well it is frustrating because I'm not even sure it's the ecm.  You can't exactly test them.  I have a chrome one that beginning last fall, I assumed was bad.  One day at the drags, it was real hard to start a couple of times.  I put an orange one on that I had and it worked fine until this weekend when it started to become hard to start.  I assumed it was bad grounds at first and as I was looking in the toolbox I noticed the chrome one that I thought was bad.  I threw it on and the car fired up.  So then I wa sure it was bad grounds all along until the chrome gave me a no start again.  This has happened hot and cold.

[8WHEELER]

I have run the Mopar Chrome box for 25yrs with no problems and yes its bolted right to the firewall, you might be running the unit to hot and you should make an aluminun bracket that holds the ECM 1in away from steel, people are doing it right and left and are not having anymore problems, I have been lucky and never gone through one.

Dan

[Ghoste]

25 years ago the components were likely sourced from the US and Japan.  I bet the current ones get all the solid state parts from China and who knows where the things are assembled.  It could be heat and vibration.  It could just be a run of bad luck.
It could be time for a different ignition system.