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P0455 (generic)

EVAP Large Leak Detected

System: Powertrain · EVAP

Severity: minor · Inspection: often fails

Description

Large EVAP leak (typically 0.080"). Check gas cap first; if cap is fine, smoke-test the EVAP system for a disconnected or cracked hose.

Diagnostic snapshot P0455

Difficulty
6/10 — Intermediate diagnostics
Est. repair cost
$120 – $450 (parts + typical shop labor)

Diagnostic workflow

  1. Confirm P0455 with a live scan — note pending vs stored and freeze frame data.
  2. Inspect wiring/connectors and related sensors before replacing modules.
  3. Clear codes and road-test; re-scan after two drive cycles if the monitor must set.

Topics

  • OBD-II and scan tools (guide)
  • Powertrain DTCs (P-prefix) (system)

Related symptoms

None linked yet.

Common fixes (curated)

None linked yet.

Related articles

Diagnostic bundle (JSON)

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