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Q: Engine lights on and engine shaking

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My engine light is blinking and the engine shakes when idling. I checked my spark plugs and they are all good but my # 4 cylinder is misfiring a lot what can I do?

My car has 14000 miles.
My car has an automatic transmission.

A: Hi, thanks for writing in. I’d be happy to ...

Hi, thanks for writing in. I’d be happy to try to help. The misfire can be caused by a few things that may be faulty: The spark plugs, ignition coil, fuel injector not firing, mechanical damage to cylinder #4, or a wiring issue to the #4 injector or coil.

If you ran a diagnostic and got the cylinder #4 misfire code, then I suggest to try swapping the #4 ignition coil with another cylinder. Clear the code then start it up. If the code now comes up as whatever cylinder you swapped the coil with, cylinder #5 for example, then you know that coil is no good.

If you would like help, consider having an expert automotive technician from YourMechanic come to your home or office to inspect and diagnose this engine issue for you, and make or suggest any repairs as needed.

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