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Q: Cylinder 3 is misfiring

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I am getting a Check Engine code P0303, which is a misfire on cylinder 3. I am not exactly sure whether the cylinder needs cleaning or replacing, or if it is just a spark plug.

Misfire on cylinder 3 usually mean you have a bad spark plug or spark plug wire. If you haven’t had a tune up in a while I would recommend having a technician, such as one from YourMechanic, come out and replace your spark plugs, wires, and air filter and see if that helps. I would also have them replace the fuel filter as well since a misfire may be caused by the fuel system as well.

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