Q: My car started knocking in the engine and bucking when I started it today, what could that be?

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I started my car today and it acted like it was going to stall and started reving up, and slightly bucking. Then before it went back to normal I heard a knocking noise under the hood.

My car has 114000 miles.
My car has an automatic transmission.

You may have a misfiring coil or spark plug or a problem with the camshaft variable timing. Make sure you have a fresh oil change with correct oil viscosity and have computer scanned for codes to see what cylinders were misfiring and have those coils replaced and all the spark plugs replaced.

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