Well last week I had my emisson test at my biddy's work, he pulled the codes off my 96 JWT ecu (running in my 98):

Knock Sensor
Rear O2
Fuel pump circuit fault

My question is, does the knock sensor being on cancel out the advance timing from my ecu? My car don't feel like is missing in power but I was wondering just out of curiousity...

 

i'm guessing that the bad ks would still retard your timing but the A/F mapping would not be affected.
replace the ks (if it's actually bad) and post the results