2005 GMC P0442: What It Means & Is It Safe to Drive?
P0442 on the 2005 GMC: Evaporative Emission System Leak Detected (Small Leak). Here's what it means, what usually causes it, what repairs typically cost, and whether it's safe to keep driving.
PowertrainLow urgency
What this code means
The EVAP system has detected a small leak. Often caused by a loose or faulty gas cap or a small hose leak.
Common causes on the 2005 GMC
- Loose, damaged, or wrong gas cap
- Cracked or disconnected EVAP hose
- Faulty purge or vent valve
- Leaking charcoal canister
Symptoms
- Check Engine Light
- Often no driveability issues
Typical fixes
- Tighten or replace gas cap
- Smoke test EVAP system
- Replace damaged hoses or valves
Repair cost range
For a 2005 GMC, repairs for P0442 typically fall between $15 and $300, depending on the root cause and labor rates in your area.
Known issues on GMC
GMC P0442 mirrors Chevrolet's pattern on shared platforms. On Sierra and Yukon, the vent solenoid near the fuel tank is a common small-leak source. Check the filler neck on older models in salt-belt regions.
Most commonly affected models
Sierra 2004–2014Yukon 2004–2014Terrain 2010–2015