Nissan Check Engine Code
P0442 on Nissan
Evaporative Emission Control System Leak Detected (Small Leak)
Also covers: Infiniti
P0442 on Nissan: what makes it different
Nissan's EVAP system uses a canister vent valve and a network of hoses/o-rings that are known to develop small leaks as they age, especially on Altima and Sentra models with plastic fuel-filler necks and EVAP canisters mounted low near road debris and moisture exposure.
Most-affected engines
- QR25DE 2.5L (Altima, Sentra)
- MR20DE 2.0L (Sentra)
- VQ35DE 3.5L (Altima, Maxima)
Common model years: 2007–2018
Most likely cause on Nissan
A cracked or loose gas cap, or a leaking EVAP canister vent valve/hose that has degraded from age and road exposure.
Known Nissan engine-family issues
Nissan's EVAP canister vent valve is a frequently reported wear item on Altima and Sentra models, often failing gradually rather than all at once, which can cause intermittent P0442 codes that come and go with temperature and humidity.
Nissan-specific causes (most common first)
- Loose, cracked, or missing gas cap (very common trigger on Nissan)
- Leaking EVAP canister vent valve (common failure point on Altima/Sentra as it ages)
- Cracked or disconnected EVAP hoses near the fuel tank, often damaged by road debris or rust
- Faulty purge valve allowing unmetered air into the system
- Small crack in the fuel-filler neck or filler pipe seal
- Deteriorated O-rings at the canister or charcoal canister connections
Nissan-specific diagnostic tip
Start by simply removing and reseating the gas cap, then clearing the code and driving several cycles — Nissan's EVAP monitor is sensitive to filler neck seal issues. If the code returns, a smoke test at the canister vent valve and hose fittings near the fuel tank will usually pinpoint the leak, since Nissan routes several vulnerable hose connections low near the underbody.
Symptoms drivers report
- Check engine light
- No drivability issues
Typical repair cost on Nissan
Most Nissan owners fix P0442 for between $20 and $350, depending on which underlying cause turns out to be at fault. Start with the most-likely cause for your vehicle — A cracked or loose gas cap, or a leaking EVAP canister vent valve/hose that has degraded from age and road exposure. — before throwing parts at it.
Nissan P0442 FAQ
Why does my gas cap keep triggering this code on my Nissan?
Nissan's EVAP monitor is strict about filler neck sealing, so even a slightly worn gas cap gasket or a cap that isn't clicked shut all the way can trigger P0442. Try a new OEM-style cap if the current one looks worn.
Is P0442 an emergency on my Altima or Sentra?
No, it's a small leak detection code and won't cause immediate drivability issues, but it should be fixed before emissions testing and to prevent fuel vapor smell.
Can I drive with this code on my Nissan?
Yes, it's safe to drive, but you may notice a faint fuel odor and it will likely fail an emissions inspection until repaired.
Related codes
Drive a different make? See the general P0442 guide for cross-vehicle causes and symptoms.
Confirm P0442 on your Nissan in 60 seconds
Two cheap things and you can read P0442 on your Nissan yourself — with freeze-frame and live data, free. No subscription.
Most common fix for P0442:
Replacement gas capAs an Amazon Associate, AXLY earns from qualifying purchases. General P0442 guide →
Wear the code
All merch →Shirts, mugs and garage gear. Printed when you order, free US shipping.
