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Q: Bang

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The second i started my car "Bang" and immediately the car accelerated all by itself. Immediately shut off and started again. This time it backfired and the engine revved again. Was afraid to put in drive. No sparks no burning.....little bit of rubber smell.

My car has 138000 miles.
My car has an automatic transmission.

A: Hi and thanks for contacting YourMechanic. ...

Hi and thanks for contacting YourMechanic. The bang you heard is a backfire in the exhaust pipe. This can be caused by the ignition timing not firing at the right time. Check the camshaft sensor for any corrosion or it the plug has any burned connections. Also, check the conditions of the plug wires and spark plugs. Ensure that all of the plug wires are on the right cylinders according to the firing order. If you need assistance, a certified YourMechanic technician can be dispatched to your location to help diagnose and repair this issue.

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