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Q: Car is knocking when I hit the gas

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My car is knocking when I hit the gas and is running rough. Could it be a sensor or possibly the timing belt or another belt?

My car has 130000 miles.
My car has an automatic transmission.

A: Hello. Is the Check Engine Light on? A loud...

Hello. Is the Check Engine Light on? A loud knocking noise coming from the engine is not typically a good sign. First, check to make sure all fluids are are the right level, especially the oil. Metal shavings on the oil dipstick can be a sign of a mechanical failure. A knocking noise from the belt drive system may be an idler pulley or one of the components along the belt drive system. If you need help verifying the problem, a certified professional from YourMechanic can come to your car's location to diagnose the rough running problem and perform needed repairs.

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