987 · Fuel

P0457

EVAP System Leak Detected (Fuel Cap Loose/Off)

LOW SEVERITY

EVAP leak attributed to a loose or missing fuel filler cap.

SYMPTOMS

  • Check-engine light
  • Occasional fuel odor

LIKELY CAUSES

  • Loose or faulty gas cap
  • Cracked or disconnected EVAP hose
  • Stuck purge or vent valve
  • Failed charcoal canister

DIAGNOSIS STEPS

  • Check the gas cap seal
  • Smoke-test the EVAP system
  • Test purge and vent valve operation
  • Inspect the charcoal canister and hoses

RELATED PARTS

  • Gas cap
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