Error code

OBD2 P2421

OBD2P2421
Diagnostic Trouble Code· Standard OBD-II fault code read from the vehicle's onboard diagnostics.

What it means

Evaporative Emission System Vent Valve Stuck Open.

Severity

moderateCan drive but should address the issue soon to avoid potential emissions problems.

Summary

P2421 indicates that the EVAP vent valve is stuck open, which affects the evaporative emission control system's ability to manage fuel vapors.

Symptoms

  • Check Engine light illuminated
  • No other noticeable symptoms

Common Causes

  • Defective leak detection pump
  • Faulty vent/purge valves or control solenoids
  • Damaged wiring and connectors
  • Split, cracked vacuum lines
  • Incorrectly installed fuel filler cap
  • Clogged charcoal canister

Diagnosis

  1. Check for visible damage in wiring and connectors
  2. Inspect vacuum lines for cracks or splits
  3. Test vent valve control solenoid with a scanner
  4. Use smoke machine to detect leaks around fuel filler cap

Fixes

  • Replace faulty components such as the leak detection pump, vent/purge valves, and control solenoids.

FAQ

What does P2421 mean?

P2421 means that the EVAP vent valve is stuck open, affecting how fuel vapors are managed in your vehicle.

How do I fix P2421?

Fixing P2421 involves replacing faulty components like the leak detection pump or control solenoids and repairing any damaged wiring or vacuum lines.

View source

Not affiliated with OBD2. Answer summarized from the manufacturer's manual linked above; consult that source for the authoritative procedure.

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