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P0455 Code: EVAP Control System Leak Detected Gross/Large Leak
P0455 means the EVAP system detected a large fuel vapor leak. Learn the common symptoms, causes, severity, and typical repair costs.
The P0455 code means the EVAP system detected a large fuel vapor leak. It is stored when the engine computer sees a signal or operating condition outside the expected range.
Emissions codes often involve EVAP vapor control, exhaust gas recirculation, catalytic converter monitoring, or oxygen sensor feedback. The right fix depends on live data, freeze-frame information, service history, and whether other codes are present.
Symptoms
- Check engine light
- Fuel smell
- Failed emissions test
- Gas cap warning
- Usually no loss of power
- Hard starting after refueling in some cases
Common Causes
- Missing or loose gas cap
- Broken EVAP hose
- Faulty vent valve
- Faulty purge valve
- Cracked charcoal canister
- Fuel filler neck leak
Severity
Low to moderate. It typically will not cause immediate drivability issues, but a large vapor leak should be repaired.
Typical Repair Costs
$20 to $700
- The lower end usually covers inspection, cleaning, wiring repair, or a simple sensor replacement.
- The higher end applies when parts are hard to access or when the code is caused by a larger mechanical, emissions, or transmission problem.
- Always diagnose before replacing parts, because one code can be triggered by several related systems.
Frequently Asked Questions
What does code P0455 mean?
P0455 means the EVAP system detected a large fuel vapor leak. The exact cause should be confirmed with diagnostic data before replacing parts.
Can I drive with a P0455 code?
It depends on symptoms. If the car runs poorly, overheats, stalls, shifts harshly, or the check engine light flashes, limit driving and diagnose it promptly.
What is the most common fix for P0455?
Common fixes include addressing missing or loose gas cap, broken evap hose, faulty vent valve, but testing is needed to avoid replacing the wrong part.
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P0440 Code: Evaporative Emission Control System Malfunction
P0440 means the EVAP system has a general vapor control fault. Learn the common symptoms, causes, severity, and typical repair costs.
P0442 Code: EVAP Control System Leak Detected Small Leak
P0442 means the EVAP system detected a small fuel vapor leak. Learn the common symptoms, causes, severity, and typical repair costs.
P0456 Code: EVAP Control System Leak Detected Very Small Leak
P0456 means the EVAP system detected a very small fuel vapor leak. Learn the common symptoms, causes, severity, and typical repair costs.
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