Here is what i want to do.. And here are the questions i have about it.

put a 95 pcm and wiring harness in a 93 chassis. I will be using the 4 wire o2's and 95 opti, timming chain, and timming chain cover. I will have the maf eliminated when i get it tunned. The reason i want to do this is for tunning issues. Nobody around me dyno tunes the 93 and sometimes mail orders just don't cut it. My main question is.. will the diagnotics port read the new pcm? Will i run into problems with the vats system? thanks for the help guys.

 

Is your trans an A4 or M6? The 95 PCM will be looking for the "E" part of the 4L60E, which can not be found on your 93. It will set DTC codes. If its an M6, it will be looking for "skip shift" which is not on the 93's, but that's a no-brainer to bypass.

The 95 will also be trying to fire the injectors in "sequential" mode.... one injector at a time, in the firing order of the engine. The 93 is set up for "batch fire" mode, where each side of the engine fires on each crank rev. Can't see why it won't work with the 95 harness. Not sure how this affects the fuel rail pressure with the 93 rails being a different design.

You might want to check the VSS interface as well.... just a possibility there is an ouput mismatch between the 93 and 95.... not positive.

 

its a th350. I am not worried about any of the guages working. I am only worried about being able to dyno tune the car with the 95 pcm. If i go through with this i will try and get a 95 pcm for a m6. thank you for the help.

 

You don't need to buy a trans-specific PCM.... any PCM can be programmed for the A4 or M6. The only "gauges" that are fed by the PCM are the speedo and the tach. Tach should work fine off the 95 PCM

 

Keep me posted on how this works for you. I have considred this as well.