OBD-II diagnostic trouble code
P0442Safe to drive
Evaporative Emission System Leak Detected (Small Leak)
The same EVAP pressure test as P0455, but detecting a smaller leak — often a hairline crack in a hose or a slightly worn fuel cap seal rather than something loose or missing.
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Code names are compiled from open/standardized SAE and ISO references. Explanations, symptoms, causes and fixes are original. Covers generic (P0/C0/B0/U0) codes only — manufacturer-specific codes are planned for a future update.
Frequently asked questions
Can I drive with P0442?
In most cases, yes — P0442 is generally not an urgent safety issue and the car is usually safe to drive for a while. Still, get it checked soon, since the underlying cause can affect fuel economy or emissions the longer it's left.
How much does it cost to fix P0442?
The cost varies too much by cause and vehicle to give a single figure here — a diagnosis will narrow it down.
What causes P0442?
Reviewed by Artyom SemenovAutomotive Editor · Fact-checked by Yauheni Kapliarchuk, Editor-in-Chief