P0440 — EVAP System Malfunction (Generic)

P0440 is a generic evaporative emission (EVAP) system fault. The EVAP system captures fuel vapors from the tank and routes them through the charcoal canister to be burned by the engine instead of vented into the atmosphere. P0440 is set when the ECM detects that this sealed system has lost its ability to hold pressure or vacuum during a leak test. It is almost always the first sign of a small leak somewhere between the fuel tank and the engine intake.

Severity: low powertrain Safe to drive (short term)

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2010-2014

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2020-2024