P0455: Evaporative Emission Control System Leak Detected (Gross Leak)
Can you still drive? Yes, the vehicle drives normally. However, fuel vapors are being released into the atmosphere, so address it when convenient.
What Does P0455 Mean?
Code P0455 indicates that the EVAP system has detected a large vapor leak. This is a more significant leak than P0442 and usually points to a missing gas cap, a disconnected EVAP hose, or a major component failure in the evaporative emission system. The gross leak designation means the system cannot maintain any meaningful pressure.
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Browse OBD-II Scanners on AmazonCommon Causes
- Missing or severely damaged gas cap
- Disconnected EVAP hose
- Cracked charcoal canister
- Stuck-open purge or vent valve
- Large crack in fuel tank filler neck
Symptoms
- Check engine light on
- Noticeable fuel odor near vehicle
- Increased fuel vapor emissions
- Possible slight decrease in fuel economy
Diagnostic Steps
- 1Verify gas cap is present and properly seated
- 2Perform visual inspection of EVAP hoses and connections
- 3Conduct EVAP smoke test to find large leak
- 4Test purge valve and vent valve operation
- 5Inspect charcoal canister for cracks
- 6Check fuel filler neck for damage
Recommended Parts & Tools
EVAP purge valve
charcoal canister
Estimated Repair Cost
| Type | Estimated Cost |
|---|---|
| Total Repair Cost Range | $15 - $500 |
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Chat with AI About P0455Commonly Affected Vehicles
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Frequently Asked Questions
What is a gross leak in the EVAP system?
A gross leak means the EVAP system has a large leak and cannot hold any pressure. It is often caused by a missing gas cap or disconnected hose.
Is P0455 different from P0442?
Yes, P0455 indicates a large leak while P0442 indicates a small leak. P0455 is usually easier to find because the leak is bigger.
Community Fix Reports
Community reports are user-submitted and not verified by Auto AI Buddy. Results may vary.
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