P0455
EVAP System Large Leak Detected
low
i Description

A large leak has been detected in the EVAP system. The leak is equivalent to a 0.080-inch (2mm) hole or larger. The most common cause is simply a loose or missing fuel cap.

? Common Causes
! Symptoms
# Diagnostic Steps
  1. Check fuel cap — is it present, tight, and not cracked?
  2. Inspect all EVAP hoses visually for disconnections
  3. Smoke-test EVAP system
  4. Check charcoal canister for damage
Typical Fix

Tighten or replace the fuel cap. Reconnect any disconnected EVAP hose.

Parts Needed
Fuel cap
Estimated Cost
$10-$300
Related Codes
Q Frequently Asked Questions
Yes. Check your fuel cap first — this solves the problem more than half the time. The code may take a few drive cycles to clear after tightening the cap.
Absolutely. Check and tighten the fuel cap. If it is worn, replace it ($10-$20). If the code persists, a visual inspection of EVAP hoses may reveal a disconnected line.
Fuel cap: $10-$20. If it is something else, a smoke test ($80-$120) will find the leak, and the repair is usually $50-$200.
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