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Q: Car misifires under load, P0300 code

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My car has been idling fine. However, when the car is under load, it starts misfiring. I had the code reading of the vehicle and the P0300 error code appeared. What do you think is the matter with my car?

A: Hello. The P0300 code refers to a detection...

Hello. The P0300 code refers to a detection of a misfire in one of the cylinders. If the car idles fine and only acts up during acceleration with this code coming up, then it is usually caused by a fuel system issue. A weak fuel pump will cause low pressure and this will occur. There are other sensors that can also cause this but the pump is the most common. I usually check the fuel pressure first. If you are planning on having this repaired, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose the misfiring issue more thoroughly and make any repairs that are needed.

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