Hi folks. I got a question. Anyone else having problems getting good ignition modules?

Backstory: When I got my car on the road about 14 years ago, it had no ignition module on the junkyard engine I built up for the car. Bought a module (don't remember the brand) and it had constant cut-out and backfiring problems. Went through two and never fully resolved the problem. Bought a junkyard module and the car ran flawlessly for 13 years.

About 3 months ago, it started cutting out intermittently. I bought a Carquest "premium" module. This worked for about 1500 miles and then left me stranded out of state. Got it replaced and the replacement lasted about 2000 miles before leaving me stranded again. Got a refund and ordered an original equipment ACDelco module.

I have checked the connector and re-tensioned the terminals; replaced all three coils / plugs / wires (and measured them each time there is a problem - all good); made sure all grounds are good, and all battery positives are good; made sure alternator voltage regulator is good. Nothing else is glitching indicating power issues. Also new crank position sensor has been installed with no effect. (This is a fast-start system which does not depend on the cam sensor for firing.)

The Carquest modules both failed in exactly the same way. They started first thing in the morning and ran normally for about 20 minutes. Then I stopped at a shop for about 15 minutes and returned to the car. It never fired the first hit. No RPM signal to the ECM and no spark. Swapping back in the original (but intermittent) 14 year old module gets the car running again instantly.

Any thoughts? Are these modules really THAT defective? I would like to have way to ensure no further problems. Now I carry a spare in the trunk, and the tools to change it. But I would like to know if I am the only one fighting this horrible battle.

The Carquest module is a CBJ1002 and the ACDelco is D1977A / 19245558

The module fits a 1994 model 3800 engine.

Sincerely,
David