1997 ford expedition 190k miles. Engine was missing. code said it was miss firing in the third cylinder. Replaced all ignition coils and sprak plugs also fuel pump. After 100 miles it started with the same symtoms? What else could it be?


It could be a bad computer that doesn't fire the fuel injector on that cylinder. Or, the fuel injector is clogged on that cylinder.

The fuel injector should have a telltale click when listening to it operating on that cylinder, and it should also make a noid light blink indicating current is getting to the fuel injector, when the fuel injector harness is connected to a noid light.

Good luck on this repair.


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