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Q: Can't get power at all. Misfire with code P0303.

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Can't get power at all.. misfire p0303

My car has 65000 miles.
My car has an automatic transmission.

Hi there. The code P0303 means that cylinder number 3 has a misfire. There are three ways that the cylinder number 3 can be misfiring.

  • Spark plug is fouled out and not creating a strong enough spark to ignite the fuel
  • Fuel injector is clogged or has stopped working and not spraying any fuel
  • A burned valve, burned piston rings, or a hole in the piston that will cause the cylinder temperature to drop causing the fuel to not burn

Check the spark plug on the cylinder number 3 and see if there is a suffucient amount of spark. If the spark is there and is strong, then check the fuel injector and see if it’s spraying or not by unplugging the injector as the engine is running. If the engine try’s to stumble more, then the fuel injector is working. If there is no change, then the fuel injector is not working. If the spark plug and fuel injector is working, then there could be internal damaged to the cylinder. If you need further assistance with your engine misfiring, then seek out a professional, such as one from Your Mechanic, to help you.

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