I have a 1981 Grand Prix with the 3.8 V6 as a daily beater. The Check Engine light has never worked and I want to keep the CC carb system intact and working. It won't light with the key in the on position or any other time. I checked the printed circuit on the back of the cluster, it's fine. Bulb's good too, and it lit when I had the cluster out and put 12V on it's circuit path from the connector.
I guess the next thing short of the ECM to look at would be the lamp driver Would anyone know what this thing looks like, and where would I find it in this car? Any other suggestions are welcome as well (except for ditching the CCC, not an option)

Thanks!!

 

84,

I'm not 100% certain on the earliest ECMs, but the "lamp driver" circuit that the service manual describes is within the ECM itself. I'd start checking connections there and around the diagnostic connector.

 

Found the problem. I don't know how or why I didn't notice this before, but this thing has a non-CC carb on it. Went to replace some vac lines and noticed a bunch of un-plugged connectors laying there. Then I noticed the lack of connectors on the carb. My bad!!
Now the question is, since the CCC system's already been botched up, should I find a cc-Dualjet to put back onto there and hope the ECM's still good, or finish the job and find a vac-adv dist for it?

 

It'll probably run you about the same either way. Personally, I'd swap to a qjet. Everyone I know who's done that to a 3.8 2bbl has gotten a little more power and slightly better mileage. There's a factory 4bbl intake for those motors (rather, it was for the 4.1L) and it's usually cheap to get ahold of. I know the people in the Before Black section of turbobuick.com can point you to it. That's where I end up for most my 3.8L questions anyway.