What would cause Misfire in cylinder 4 in a 2002 Saturn SC1 I have spark New plugs wire coil module Any ideas?

Answer 1

Misfire can be caused by many different types of problems with your valves. It could be burned or leaking valves, carbon build up on the valves, weak or broken valve springs, worn valve guides or lifters, broken worn or bent rocker arms or pushrods, worn camshafts, improper valve timing, or worn pistons or rings. A misfire is basically when the cylinder is not producing enough air-fuel mixture properly, so your valves may not be supplying the proper amount of air into the cylinder, for the compression to be strong enough for combustion. Faulty: plug, plug wire, ignition coil, ignition module, fuel injector are the most common. Coolant leaking into a cylinder is another. Internal engine problems such as burnt valve, broken valve spring, bent push rod, worn rings.....