P0440 on a Toyota: Causes, Fixes & Repair Cost

🟢 Low severity · drivable

Safe to drive — this is a general emissions-system fault, not an engine problem. Fix it before your next emissions test.

What P0440 means on a Toyota

On a Toyota, P0440 means the engine computer detected a general problem in the evaporative emission (EVAP) system that captures fuel vapors from the tank. It is the catch-all EVAP code, less specific than the leak-size codes P0442, P0455, and P0456, so it often shows up together with other EVAP codes. The engine usually runs and drives normally.

Is P0440 common on Toyotas?

P0440 is a common EVAP code on Toyotas like the Camry, Corolla, RAV4, and Highlander, most often as the gas cap seal and EVAP hoses age. A loose or worn gas cap is the first thing to check, followed by a failing purge valve and small cracks in the EVAP hoses. Cold weather can make the code appear more often.

Commonly reported on: Camry, Corolla, RAV4, Highlander.

Symptoms

Check engine light is on
Possible faint fuel smell
Usually no driving symptoms

Common causes

most common: Loose, missing, or damaged gas cap
common: Faulty EVAP purge valve
common: Small leak in an EVAP hose or fitting
less common: Faulty vent valve or charcoal canister

How to fix it

Fix	DIY?	Typical cost
Tighten or replace the gas cap	Yes	$10–30
Inspect and replace cracked EVAP hoses	Yes	$15–80
Have a smoke test performed to find the exact leak	Mechanic	$50–150
Replace a faulty purge or vent valve	Yes	$40–160

Frequently asked questions

Can I drive my Toyota with a P0440 code?

Yes. It is a general EVAP system fault and does not affect how the Toyota runs. Fix it before your next emissions test.

How is P0440 different from P0442 on a Toyota?

P0440 is the general EVAP fault code and is less specific. It often appears with other EVAP codes, so a smoke test is the best way to find the actual leak.

How much does it cost to fix P0440 on a Toyota?

Usually under $200. A gas cap costs about $10–30, a smoke test runs $50–150, and a purge valve replacement is typically $40–160.