Q: Sporadic misfiring, check engine light on sometimes

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My car has been misfiring sporadically during driving. It occasionally occurs when I start the car as well. The dash sometimes shows the check engine light on. I had the spark plugs replaced. The coils are replaced with new ones as well. The mechanic ran diagnostics, and there are no codes related to cylinder identification. What should I do?

Hello there. If there is no cylinder specific misfire codes, it may be a random misfire situation. Without the exact code, I cannot give a precise answer for your specific situation but can offer a possibilities. The most common causes of a multiple cylinder misfire are the camshaft position sensor, fuel pump, crank sensor, fuel line, or an ignition fault. A qualified technician, like one from YourMechanic, will be able to diagnose the misfiring issue and perform any repairs required. Given that the fault is intermittent it may take a few attempts for the fault to be duplicated.

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