Q: Knock sensor 1

asked by on November 02, 2016

My engine light came on the other day. I scanned it with my OBD2 scanner and it came back saying "Knock sensor 1 Circuit low bank 1 or single sensor." I read online that since i got this warning i should be experiencing loud bumps or vibration but i am not experiencing any of this. I was wondering if i have a faulty sensor. What do you think?

My car has 192000 miles.
My car has an automatic transmission.

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Hello there. The knock sensor code can have various causes on your 2004 Chevrolet Silverado. The knock sensor circuit low, bank 1 code is telling us that the knock sensor in bank 1 that it has low circuit voltage. This low voltage is caused by either a wiring harness fault to the knock sensor, or an internal fault to the sensor.

If the engine is knocking the knock sensors, it will detect it and retard the timing to prevent knocks, not trigger the Check Engine Light for low voltage. If you would would like to have a professional technician diagnose your knock sensor fault in person, consider YourMechanic, as a certified technician can come to your car’s location to pinpoint the problem.

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