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Knock Sensor

I have a 1996 cavalier with a knock sensor code coming up on the check engine light. Put in a new sensor still getting the code . put in new plugs and wires still no luck. Car runs great anyone have any ideas to fix this problem.

This may be a case where some “snapshots” (with a scan tool) will be needed to identify whats going on when the code is generated,or it could be a wiring failure,corrosion,rodent damage? I have seen all three with the Caviler.

Exactly what code or codes is it? Getting any rattling on acceleration with a warmed up engine?

Keep in mind that if you have a specific knock sensor code that does not necessarily mean the knock sensor itself is bad; only that a problem exists in that circuit. It could be the wire harness, wire connector, ECM fault, etc.

Some knock sensor problems happen when there is a tapping sound that is interpreted as a knock. If you have a bad lifter or a loose wrist pin (on a piston) or a rumbling bearing on an accessory, you could also notice a loss of performance due to the timing being retarded when the knock sensor tries to do its job.

po325 knock sensor 1
circuit malfunction
bank 1 or sensor 1

If you hit speed bumps, or drive on a bumpy road, you might set the knock sensor code.