P0455
Evaporative Emission System Leak Detected (Large Leak)
This means your car's computer has found a significant leak in the system designed to capture fuel vapors, often indicating a loose gas cap or a larger crack in a hose.
The Powertrain Control Module (PCM) has detected a large leak in the Evaporative Emission (EVAP) system.
Common causes
- high
Loose, missing, or faulty gas cap
This is the most common and easiest fix; check the gas cap for proper sealing and tightness.
Typical part cost: $0-30 part
- medium
Cracked or disconnected EVAP hose
Inspect all visible EVAP hoses for cracks, breaks, or disconnections, especially near the fuel tank and engine.
Typical part cost: $20-100 part
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First things to check
- 1Tighten or replace gas cap
- 2Visually inspect all EVAP hoses for cracks or disconnections
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Related codes
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Frequently asked questions
Will a P0455 code cause my car to fail emissions?
Yes, a P0455 code indicates an EVAP system fault, which is a common reason for failing emissions tests.
Can I fix a P0455 myself?
Often, yes. Checking and replacing the gas cap or a visibly cracked hose are common DIY fixes. More complex issues may require professional tools like a smoke machine.
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