Check Engine Codes / P0442
P0442 Code
Evaporative Emission System Leak Detected (Small Leak)
What it means
Same system as P0455 but a smaller leak — often a pinhole in a hose or a slightly imperfect gas cap seal.
Can you keep driving?
Yes, no mechanical risk.
Common causes
Listed most-common first. Fix cost depends on which one it turns out to be — check your quote free below.
⚠️ Don't get ripped off
Small EVAP leaks genuinely require a smoke test to find, and that diagnostic charge is fair — but a parts-cannon approach of replacing valves one at a time on your dime is not. Ask for the smoke-test result before approving any parts.
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Related codes
Informational only — codes share symptoms across vehicles, so proper diagnosis on your specific car always comes first.