I wired in an LT1 into my '86 Z and I still cant get it to scan on the ALDL. The service engine soon indicator works fine, and I hooked up the serial data and diagnostic wires and it still doesnt work...harness is a '97 and computer is a '94 OBD1 and I wired it as a '97. Engine runs but runs pig rich, and I need to scan it to see what is going on with it.

I dont know if it's a wiring problem in the dash (did that with the 305 TPI that was in there too) or if it's a problem with the connector compatability... I still have the stock ALDL in there. I wired it from the end of the LT1 harness and tapped it into the original ECM harness connector. Anybody have any ideas?

 

Is the PCM a '97 model? If it is, make sure you have the correct program for it, also the ALDL's aren't powered, you have to be running power to the cable you have for it to work properly.

http://www.akmcables.com can show you.

 

No if I remember correctly I had it tuned for an OBD 1 conversion... I sent the '97 PCM and an OBD 1 PCM to the tuner in exchange for the tune. I specified that I was still using the '97 harness too.

My scanner is an auto X-ray... runs off its own batteries. Works fine in my '94. Doesnt require external power like a Tech 1.

I hooked up the serial data and diagnostic wires and it refuses to work, but I've seen on here several different ways to hook it up. Im thinking its in the chassis harness so I am going to jump it to the back of the ALDL to bypass the chassis harness tomorrow; I have it connected right now to the back of the original ECM connector from the LT1 harness.

Tired. Time for bed

Thanks for the link too...gonna try tomorrow.