Worn spark plugs or ignition coils. Vacuum leak. Low fuel pressure. Faulty camshaft or crankshaft position sensor. EGR valve stuck open.

Which cars are affected by P0300?

P0300 is most commonly reported on Ford, Vauxhall, BMW, Mercedes-Benz, Audi vehicles, but can appear on any make.

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P0300

High severity

Random/Multiple Cylinder Misfire Detected

The engine is misfiring across multiple cylinders rather than just one. This can cause rough idling, loss of power, and increased emissions.

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Common causes of P0300

1Worn spark plugs or ignition coils

2Vacuum leak

3Low fuel pressure

+2 more causes

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Commonly affected vehicles

FordVauxhallBMWMercedes-BenzAudi

P0300 can appear on any vehicle — these are the makes where it is most frequently reported.

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Recalls & technical bulletins

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Related fault codes

P0171Medium

System Too Lean (Bank 1)

P0420Medium

Catalyst System Efficiency Below Threshold (Bank 1)

P0172Medium

System Too Rich (Bank 1)

P0401Medium

Exhaust Gas Recirculation (EGR) Flow Insufficient