What does code P0440 mean on a Infiniti and is it safe to drive?
P0440: Evaporative Emission System Control System Malfunction. Here's what it means on your Infiniti, what usually causes it, what repairs typically cost, and how safe it is to keep driving.
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What this code means
A general fault in the EVAP system—could be a leak, stuck valve, or sensor issue.
Common causes for your Infiniti
- Gas cap loose or faulty
- Purge or vent valve stuck
- Charcoal canister or hose leak
Symptoms
- Check Engine Light
Typical fixes
- Replace gas cap
- Test purge/vent valves
- Smoke test EVAP system
Repair cost range
For a Infiniti, repairs for P0440 often fall between $20 and $400, depending on the cause and whether you use OEM or aftermarket parts. Labor rates vary by location.
Known issues on Infiniti
Infiniti P0440 EVAP system fault on older VQ35 models—gas cap first, then the EVAP canister purge volume control solenoid. The canister is mounted at the rear of the engine bay and its hoses can crack from heat cycling.
Most commonly affected models
G35 2003–2007FX35 2003–2008QX56 2004–2007