P0455 – EVAP System Large Leak Detected

Description

The ECM detects a large leak in the EVAP system, often caused by a loose or damaged gas cap.

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Symptoms

  • Check engine light
  • Fuel smell
  • Poor emissions
  • Rough idle

Causes

  • Loose gas cap
  • Cracked EVAP hose
  • Faulty purge valve
  • Faulty vent valve

Diagnosis

  • Smoke test EVAP
  • Inspect hoses
  • Test purge valve
  • Test vent valve

Repair

  • Tighten/replace gas cap
  • Repair hoses
  • Replace purge or vent valve

Related Problems

Related Fault Codes