Q: Misfire in cylinder number 8.

asked by on January 07, 2017

Im getting the code P0300 and P0308 (Which I assume are related) and I've had you guys replace the ignition coil in November and that fixed it then but now the engine light is back and I am getting that code again. What could the issue be?

My car has 123000 miles.
My car has an automatic transmission.

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Hi there. The issue could be the spark plug not firing on cylinder 8, the fuel injector not atomizing on cylinder 8, or there could be a burned valve or a burned head gasket. Check the spark plug on cylinder 8 and see if its burned or fouled out. If the spark plug looks normal and has a good spark, then check the fuel injector by unplugging the harness from it. If the engine hesitates even more, then the injector was working. If there is no change, then switch the injector with the one next to it and see if the engine hesitates even more. If the engine hesitates even more, then the injector is not working. If the engine runs the same condition before the injector was swapped, then there could be a burned valve or a burned head gasket. Get a compression gauge and check the cylinder 8 and the cylinder next to it for a comparison. If the cylinder 8 is lower than the cylinder next to it, then there is an issue in the engine and it needs addressed. If you need further assistance with your misfire, then seek out a professional, such as one from Your Mechanic, to help you.

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