P0440 Code: Meaning, Symptoms, Causes & Fixes
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Causes ranked by likelihood
| Cause | Likelihood | DIY difficulty |
|---|---|---|
| Loose or faulty gas cap — Tighten or replace. | Most likely | 1/5 |
| EVAP hose leak — Visual inspection of rubber lines. | Possible | 1/5 |
| Bad purge valve — Common on older GM and Ford vehicles. | Less likely | 1/5 |
Symptoms of P0440
- CEL only
How to diagnose P0440
- Confirm the code. Read P0440 with an OBD-II scanner and note the freeze-frame data (speed, temperature, load) recorded when it set.
- Check for companion codes. Look for other stored or pending codes such as P0455, P0442 — they often point to one shared root cause.
- Check: Loose or faulty gas cap. Tighten or replace.
- Check: EVAP hose leak. Visual inspection of rubber lines.
- Check: Bad purge valve. Common on older GM and Ford vehicles.
- Clear and verify. After the repair, clear the code and complete a full drive cycle to confirm P0440 does not return.
Can I drive with P0440?
Yes, no drivability impact.
Related codes
P0440 by vehicle
- P0440 on the Ford F-150
- P0440 on the Ford Escape
- P0440 on the Ford Explorer
- P0440 on the Ford Focus
- P0440 on the Ford Mustang
- P0440 on the Chevrolet Silverado
- P0440 on the Chevrolet Equinox
- P0440 on the Chevrolet Malibu
- P0440 on the Chevrolet Tahoe
- P0440 on the Chevrolet Traverse
- P0440 on the Chevrolet Cruze
- P0440 on the Toyota Camry
- P0440 on the Toyota Corolla
- P0440 on the Toyota RAV4
- P0440 on the Toyota Highlander
- P0440 on the Toyota Tacoma
- P0440 on the Toyota Prius
- P0440 on the Honda Civic
- P0440 on the Honda Accord
- P0440 on the Honda CR-V
- P0440 on the Honda Pilot
- P0440 on the Honda Odyssey
- P0440 on the Nissan Altima
- P0440 on the Nissan Rogue
- P0440 on the Nissan Sentra
- P0440 on the Jeep Grand Cherokee
- P0440 on the Jeep Wrangler
- P0440 on the Jeep Cherokee
- P0440 on the Hyundai Elantra
- P0440 on the Hyundai Sonata
- P0440 on the Hyundai Santa Fe
- P0440 on the Hyundai Tucson
- P0440 on the Kia Forte
- P0440 on the Kia Sorento
- P0440 on the Kia Sportage
- P0440 on the Kia Telluride
- P0440 on the Kia Optima
- P0440 on the Subaru Outback
- P0440 on the Subaru Forester
- P0440 on the GMC Sierra
- P0440 on the GMC Acadia
- P0440 on the Ram 1500
- P0440 on the Dodge Charger
- P0440 on the Volkswagen Jetta
- P0440 on the Mazda CX-5
- P0440 on the BMW 3 Series
- P0440 on the BMW X5
- P0440 on the Mercedes-Benz C-Class
Frequently asked questions
What does P0440 mean?
P0440 means evaporative emission control system malfunction. P0440 is a generic EVAP system fault — your fuel vapor recovery system isn't sealing properly. Like P0455, the gas cap is the #1 culprit.
Can I drive with code P0440?
Yes, no drivability impact.
What is the most common cause of P0440?
Loose or faulty gas cap — Tighten or replace.
What are the symptoms of P0440?
CEL only.
How much does it cost to fix P0440?
A typical shop repair range is $0–$500, depending on which cause it turns out to be. Cheaper causes such as bad purge valve should be ruled out first.