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Q: I have a bad knock sensor. Is it worth replacing?

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Hello, I own a 1996 Lexus ES300 It is running great except for code P0325 always showing up. I'm guessing this code is for knock sensor. My car runs great but I have calculated my average mpg to be at 15-16. I'm guessing this is because of the knock sensor. My question is if I should replace the knock sensor or just run the car until it dies on me since my car is only worth $2000. Thank you

My car has 170000 miles.
My car has an automatic transmission.

Hello. Yes, you are correct - the P0325 is indicative of a failed knock sensor (or the knock sensor wiring). I think it is a rare circumstance where you would not want to make this repair. It is straightforward and relatively inexpensive to repair, would improve engine power and efficiency, and might also prevent poor fuel mixture issues that could clog your catalytic converter. It is an important part of your engines efficient and clean operation. I recommend having a knock sensor replacement service completed by a mobile, professional mechanic, such as one from YourMechanic. The choice is ultimately yours, but this repair could help extend the life of your car.

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