P0442
Evaporative Emission System Leak Detected (Small Leak)
This code indicates that your car's computer has found a minor leak in the system designed to prevent fuel vapors from escaping, often caused by a loose gas cap or a small crack in a hose.
The Powertrain Control Module (PCM) has detected a small leak in the Evaporative Emission (EVAP) system.
Common causes
- high
Loose, missing, or faulty gas cap
A gas cap that isn't sealing properly is the most common culprit for small EVAP leaks.
Typical part cost: $0-30 part
- medium
Cracked or disconnected EVAP hose
Inspect all EVAP hoses for small cracks, chafing, or loose connections.
Typical part cost: $20-100 part
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First things to check
- 1Tighten or replace gas cap
- 2Visually inspect all accessible EVAP hoses and connections
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Related codes
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Frequently asked questions
Can a P0442 code clear itself?
If the cause was a loose gas cap, tightening it might allow the code to clear after a few drive cycles, but it's best to manually clear it after fixing.
What is the most common fix for P0442?
The most common fix is simply tightening or replacing the gas cap, followed by inspecting and replacing any cracked or disconnected EVAP hoses.
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