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.
Looking for an estimate?
Got a quote to fix P0442?
Enter your car and the price — get an instant verdict on whether it's fair, with labor hours checked against industry book time.
Check My Quote Free →The fair price shows after you enter your quote · free, no signup
Don't have a quote yet? Get matched with a pro directly →
Looking for leads?
Get matched with local homeowners
Local contractor or shop in your area? We send you homeowners who already checked their quote and want a fair bid — no cold-calling, no signup.
Get Leads →Straight to the person who runs it · no signup
Related codes
Informational only — codes share symptoms across vehicles, so proper diagnosis on your specific car always comes first.