I just acquired a 94 Z28 to replace my stolen 87 IROC and I am in the process of fixing the minor things that are wrong with it. I get an SES occasionally on the interstate (assuming EGR problem) and I went to pull the code out but when I ground the A and B terminals on the ALDL the SES ight goes completely out. I don't even get a code 12. The fans do turn on so at least some of the diagnostic functions appear to be working. Anyone have a guess? I'm guessing a bad wire from the ECM to the ALDL. Anyone have the ECM pin out for the serial data wire to the ALDL. Thanks!

 

Grounding the pins won't work on the 94. You'll have to get a code scanner for it... or take it to AutoZone. They'll do it for free.

 

Can I do it with Datamaster? I still have it on my Laptop from when I used it on my thirdgen. Thanks!

 

Datamaster will work, but you'll have to download the version for 94-95 cars and I'm not sure if the cable will work on the 94 without modifications. (I think there was an extra resistor in it for older cars?)
It's an AKM cable, right?

 

i thought AutoZone only did obd2...but you could call them to find out.

have you been clearing the codes in the computer? just to make sure it isn't an old code taht is stuck in the computer?

 

Yeah, the cable was AKM but I will have to order a new one anyway since it was in the car. So iI have to buy a new version of Datamaster and a new cable? That sucks.