P0455: Evaporative Emission System Leak Detected (Large Leak)
What this check-engine code means in plain English, what usually causes it, and what a fix typically costs.
What P0455 means
The engine computer has detected a large leak in the evaporative emission (EVAP) system, which captures fuel vapors from the tank and prevents them from escaping into the atmosphere. This means fuel vapors may be venting improperly, and the system cannot maintain the correct pressure during self-tests.
What causes P0455?
Is P0455 safe to drive?
You can typically continue driving with this code, as it does not affect engine performance or safety. However, you may smell fuel vapors, fail an emissions test, and experience slightly reduced fuel economy until the leak is repaired.
P0455 repair cost
Industry-average estimates. Cost ranges from free (tightening the gas cap) to around $400 if hoses, valves, or the gas cap need replacement; most repairs fall under $150.
Which one is it for your car?
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