P0300 fault code of magotan crankcase ventilation device.

After the key oil-water separator and the diaphragm of the oil-water separator were damaged and leaked, the air flow meter detected that the air intake was reduced, and the ECU correspondingly reduced the fuel injection, which could not form the correct air-fuel ratio with the actual air intake, and the mixture was too thin, resulting in poor idling operation of the engine. Through CMP and CKP, ECU will report fault code P0300, multi-cylinder missing.

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