OBD-II code · generic

P0455

Evaporative Emission System Leak Detected (large leak)

System: Evaporative emission (EVAP) system
Severity: Low (1/5)
Can I keep driving?: Usually safe to drive

01

What does P0455 mean?

P0455 is defined as “Evaporative Emission System Leak Detected (large leak)”. This code indicates a leak or circuit problem in the EVAP system (canister, purge valve, fuel cap, hoses), which stops fuel vapour from the tank escaping into the atmosphere.

You can usually keep driving, but have it checked soon so a small fault doesn’t become a bigger one.

02

Symptoms

Check engine light comes on
Sometimes a smell of fuel
The pump nozzle clicking off often while refuelling (if the canister is blocked)

03

Common causes

Loose fuel cap or a cap with a damaged seal (the most common cause)
Canister purge valve failure
Cracked EVAP hoses
Blocked canister or vent valve

04

How to diagnose it

Check that the fuel cap closes fully and its seal is intact.
Open and close the purge valve with a diagnostic tool to test it.
Find the leak in the system with a smoke test.

05

How to fix it

Tighten or replace the fuel cap; the code may clear itself after a few drive cycles.
Replace the faulty valve or cracked hose.

06

Manufacturer-specific meanings

The same code can mean something different on some makes.

Kia: EVAP Emission System Leak Detected Large Leak
Dodge: Large EVAP Leak

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Related codes

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Look up another code

This page is general information; an exact diagnosis needs measurements and a technician’s check.