A knock sensor is like a small electronic microphone that is usually attached to the engine block and listens for a couple of things that a engine might do. One thing it listens for is pre-ignition or knocking inside the engine usually caused by a few issues including dirty gas, wrong engine timing low octane fuel, wrong air / fuel mixture, and also by the wrong spark plugs. It also listens for engine run on which happens when the vehicle is turned off, but tries to keep running until it stalls. Once a noise is detected, the knock sensor sends a signal to the cars computer which in turn will retard the timing at 2 degree intervals until it corrects the issue. If the knock sensor fails, it can seriously damage the engine, as continuous pre-ignition could cause melting or fractures in the pistons just to name a few.
Comes as a SET of 1
(1) - Knock Sensors X1
Replaces dealer part numbers: SU4769 KS107 220607B000
Fit for
1999-2004 Nissan Frontier
2000-2004 Nissan Xterra
1999-2002 Nissan Quest
1999-2002 Mercury Villager
2000 Nissan Pathfinder
Comes as a SET of 1
(1) - Knock Sensors X1
Replaces dealer part numbers: SU4769 KS107 220607B000
Fit for
1999-2004 Nissan Frontier
2000-2004 Nissan Xterra
1999-2002 Nissan Quest
1999-2002 Mercury Villager
2000 Nissan Pathfinder
