Q: My car backfires at 50 mph.

asked by on November 19, 2016

Car backfire from exhaust at 50 Mph. Smooths out and back fire quites at about 65.
My car has an automatic transmission.

Hi there. There is a timing problem with your engine. Check the vacuum advance to see if its advancing when the engine is at a higher rpm. Also check the spark plugs and wires for if they are burned but functional, they can cause a delay and make the ignition fire as the exhaust valve is about to open. If you need further assistance with your engine backfiring at highway speeds, then seek out a professional, such as one from Your Mechanic, to help you.

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