Chevy & GMC Vans

Just bought a 1998 awd safari that throws a knock sensor code (the knock sensor is new) and runs really rough when warmed up from about 40 mph on The shop that replaced the knock sensor (which did not fix the problem) now tells me the engine is a 2002 and there may be some computer compatibly problems and or the computer components are not wired properly I'm guessing pcm? they want $90 bucks on top of the $160 they charged me for the $50 knock sensor to "diagnose the problem" any input would be hugely appreciated while I am fairly mechanical trouble shooting computer componitry is not my strong point Is it possible that the knock sensor simply has a short or is not wired to the pcm properly or at all causing bad timing?

The 2002 PCM is different from what I've read, but that should not effect your situation if you have a 2002 engine and your original 1998 PCM and harness. I don't know of any differences in the sensors, etc, although I did read somewhere about a knock sensor with 2 wires. My 99 had only one wire, your 98 should be the same.

As long as the PCM and harness are original or at least compatible, there should be no miswire issues.

I don't think you can swap in a 2002 PCM without changing the 4 colored connectors, since they are different. I don't know if they pin out differently, but I know Scott (sfeaver) just did this and hopefully will give his opinion. Scott stated that the 2002 PCM is more capable.