How does the knock sensor work and could it be faulty? It's supposed to tell the ECM to adjust your timing if pinging is detected right? Just throwing it out there...

 

The KS is a piezo sensor set to detect the frequency of a knock, if it does it tells the ECU to retard the timing accordingly. I have no idea how one would test it, maybe with an oscilloscope and a signal generator set to the right frequency or something. I don't want to have to replace it since the cheapest I've found them is $250. Besides, even if the KS is bad there's something else going wrong anyways and, if it is working, it shouldn't have to be working all the time. If anyone knows how to test the KS I'd love to know so I can potentially eliminate it as the problem. Thanks for the suggestion.

 

After some probing and testing I thought there was a pretty good chance the TPS might be the culprit so I put in a new one and unfortunately that's not the case ($70 down the drain ). I'm starting to think it might just be a broken wire or bad connection or a short somewhere so I'll be giving the multimeter a good workout in the next day or two. I'll update with results.

 

I know this is an old thread, but what did you do to fix the high compression and pinging? I'm having the same issue and have tried everything mentioned in this thread to fix it.
Thanks!