OBD-II TROUBLE CODE

P0440

P0440 means "Evaporative Emission (EVAP) System Malfunction". Severity: 🟢 Low. Usually safe to drive in the short term, but get it checked soon.

What the P0440 code means

CodeP0440
DefinitionEvaporative Emission (EVAP) System Malfunction
SystemPowertrain (engine & transmission)
TypeGeneric (SAE standard)
SubsystemAuxiliary Emission Controls
Severity🟢 Low

Common causes of P0440

How to fix P0440

Always confirm the diagnosis with a scan tool and live data before replacing parts.

Is it safe to drive with P0440?

Usually safe to drive in the short term, but get it checked soon.

FAQ

P0440, answered.

What does P0440 mean?

P0440 stands for "Evaporative Emission (EVAP) System Malfunction". It is a generic (sae standard) OBD-II powertrain trouble code.

Is it safe to drive with a P0440 code?

Usually safe to drive in the short term, but get it checked soon.

What causes P0440?

Common causes include: Loose or faulty gas cap; EVAP hose leak; Failed purge/vent valve.

How do you fix P0440?

Typical fixes: Tighten or replace the gas cap; Inspect EVAP hoses; Test purge and vent valves. Always confirm the diagnosis before replacing parts.

Related codes

P0401 · P0420 · P0430 · P0442

Look up another code