Faulty ignition coil on cylinder 1. Worn or fouled spark plug. Fuel injector failure. Low compression (burned valve, head gasket). Vacuum leak near cylinder 1 intake runner.

Which cars are affected by P0301?

P0301 is most commonly reported on Ford, BMW, Vauxhall, Volkswagen, Mercedes-Benz vehicles, but can appear on any make.

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P0301

High severity

Cylinder 1 Misfire Detected

A misfire has been specifically detected in cylinder 1. The ECU has identified that this cylinder is not producing the expected power contribution, causing rough running and potential catalyst damage.

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Common causes of P0301

1Faulty ignition coil on cylinder 1

2Worn or fouled spark plug

3Fuel injector failure

+2 more causes

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Commonly affected vehicles

FordBMWVauxhallVolkswagenMercedes-Benz

P0301 can appear on any vehicle — these are the makes where it is most frequently reported.

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Related fault codes

P0171Medium

System Too Lean (Bank 1)

P0300High

Random/Multiple Cylinder Misfire Detected

P0420Medium

Catalyst System Efficiency Below Threshold (Bank 1)

P0172Medium

System Too Rich (Bank 1)