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Q: Check Engine Light is on - code P0328

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I just had my vehicle in for regular service. While being serviced it was noted that my cylinder head was leaking as well as the vacuum pump. The technician replaced the valve cover gasket, resealed the cylinder head cover as well as resealing the cover and replacing the seal for the vacuum pump. I drove the car home later that day with no issues. Upon starting the car up 4-5 hours later to go to dinner, the check engine light came on. I went the next day to the local AutoZone to have the code ran, and was told it was a P0328 Knock Sensor Circuit High Input. My question is first, how serious a problem is this? As in, should we get the vehicle in to the shop tomorrow, or can it wait the four days until the weekend. Second, based on the work done to my vehicle would that in anyway be able to cause this code to happen?
My car has an automatic transmission.

A: Hi there. A failure of the engine knock sen...

Hi there. A failure of the engine knock sensor is a somewhat risky issue with a turbocharged engine such as yours. Turbocharging increases cylinder pressure during operation and makes the engine more likely to experience "pre-detention" or knocking. The knock sensor is critical in detecting this and retarding engine timing to avoid this destructive issue. If it is essential to drive a few days with this problem, take care to keep your foot out of the gas as much as possible. Yes, it is possible that replacing the valve cover gasket required the knock sensor to be disconnected. Your problem may be solved by simply reconnecting an unplugged cable. I would check with the service center that replaced the valve cover gasket just in case.

If you need any assistance, then I recommend having a certified technician, such as one from YourMechanic, come to your location to determine why the Check Engine Light is on and suggest the necessary repairs.

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