Q: Knock sensor keeps setting off

asked by on May 15, 2016

So I've have been driving my Mazda as a daily driver for a while now. Just the other day I got my check engine light and I hooked up my code reader. I got the code P0328 (knock sensor) and I'm not sure what would set that off. I'm running ethenal free fuel, the car seems to be running fine and doesn't have any unusual noises. Just wondering what I should start doing next.

My car has 141000 miles.
My car has an automatic transmission.

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I would recommend clearing the P0328 code and then see if the code returns. If the code returns and the engine does not have any knocking noise, then test and replace the knock sensor and retest the system. If the code returns, then have a follow up check done to see if the knock sensor is detecting a knock that is hard to hear without a specialized listening device; the engine may be having an internal knock setting off the knock code so the Check Engine Light would need to be diagnosed.

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