Q: I hear a knocking sound coming from the engine.

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I hear a knocking sound coming from the engine and looked at all the valve springs and they are good. I hear the sound the most just under 2 thousand rpm and barly hear it at any other engine speed. The acceleration didnt decrease or anything. How could you test a bad knock sensor

My car has 160000 miles.
My car has an automatic transmission.

Hi there. The sound could be the lifters sticking and not getting oil to them. This would be for the noise lessens as the rpm’s goes up. Add 1 quart of ATF Type F to your engine oil and run the engine at 3,000 rpm for 15 minutes. Then drain out the engine oil and replace the filter. Add new engine oil and a new oil filter. Start the engine and see if the noise is still present or has gone away. If the noise is still present, then the lifters need replaced.

To check the knock sensor, check to see if power is going into the sensor and back probe the wire to see if there is power coming out. If the engine light is not on, then the engine knock is not strong enough to cause a vibration to trigger the sensor. If you need further assistance with the knocking noise that you are hearing from the engine, then seek out a professional, such as one from Your Mechanic, to help you.

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