Why does your car shoot flames from the exhaust?

Answer 1

Flames coming out the exhaust is the result of the exhaust igniting fuel that was not burned inside the engine. Occasional pops of flame can be from backfiring, which shoots out unbirned gas that gets ignited from the heat of the exhaust. On cars without electroinc ignition or fuel injection, which covers all older cars, turning the ignition off while moving and then back on can result in a backfire and flames.