Fault-Code Library · EVAP
P0442: EVAP system small leak detected
The fuel-vapor system cannot hold the small vacuum or pressure change expected during the leak test.
Common symptoms
- •Engine warning light
- •Fuel smell
- •Usually no drivability symptom
Likely causes
- •Loose or damaged fuel cap
- •Small cracked EVAP hose
- •Purge or vent valve leak
- •Charcoal canister or seal issue
First checks
- •Inspect the fuel cap and seal
- •Smoke-test the EVAP system
- •Command purge and vent valves while monitoring sealing behavior
Important
Small EVAP leaks are often simple, but guessing parts can get expensive quickly.
A fault code identifies a detected condition, not a failed part. Confirm manufacturer-specific subcodes and live data.
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