Faulty EVAP canister purge valve. Damaged or missing fuel cap. Cracked EVAP hoses or canister. Vent valve malfunction. Fuel tank pressure sensor fault.

Which cars are affected by P0440?

P0440 is most commonly reported on Toyota, Ford, Vauxhall, Nissan, Honda vehicles, but can appear on any make.

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P0440

Low severity

EVAP Emission Control System Malfunction

A general fault has been detected in the evaporative emission control system. This system captures fuel vapours from the tank and feeds them into the engine to be burned.

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Common causes of P0440

1Faulty EVAP canister purge valve

2Damaged or missing fuel cap

3Cracked EVAP hoses or canister

+2 more causes

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Commonly affected vehicles

ToyotaFordVauxhallNissanHonda

P0440 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)