P0442: Evaporative Emission Control System Leak Detected (Small Leak)
What this check-engine code means in plain English, what usually causes it, and what a fix typically costs.
What P0442 means
The EVAP system prevents fuel vapors from escaping into the atmosphere by storing them in a charcoal canister and routing them back into the engine. This code means the system has detected a small leak, typically equivalent to a hole about 0.040 inches in diameter, which allows vapors to escape.
What causes P0442?
Is P0442 safe to drive?
This code does not affect vehicle safety or drivability, so you can continue driving normally. However, the leak allows fuel vapors to escape, which increases emissions and may slightly reduce fuel economy, so you should have it diagnosed and repaired within a few weeks.
P0442 repair cost
Industry-average estimates. Cost depends on the source of the leak, ranging from a simple gas cap replacement to EVAP canister or valve replacement requiring more labor.
Which one is it for your car?
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