Stan et al.,

To oversimplify, a knock sensor is a microphone. It listens for the sound of
a knocking engine. Then tells the ECU to make adjustments to the timing until
the knocking stops.

They are quite sensitive. I have heard of knock sensors not working properly
because they are not properly torqued. I guess if it's too tight it can't
listen as easily. It's like you trying to listen and somebody holding a
pillow against your ear. the tighter they push the pillow to your head the
more difficult it is to hear. Pretty soon you can't understand anything
anyone is saying. I would guess the same thing happens to the knock sensor.

BenT
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