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EmissionsSeverity Low: usually safe to drive

P0442Evaporative Emission System Leak Detected (Small Leak)

What it means

The EVAP leak test found a small leak (about 1 mm or more).

Symptoms

  • Check engine light
  • Possibly a fuel smell
  • Usually no change in how the car drives

Common causes

  • Loose or worn fuel cap seal
  • Cracked EVAP hose
  • Leaking canister or vent valve
  • Leaking filler neck

What to check first

  1. Check and replace the fuel cap seal if worn
  2. Smoke-test the system with the vent valve closed
  3. Inspect hoses near the tank and the canister
Can I drive with P0442? Usually yes. P0442 rarely affects how the car drives, but it keeps the check engine light on and can fail an emissions test.

Generic OBD-II meaning. Manufacturer-specific meanings and checks can differ; always check the service information for the car.

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P0442: questions and answers

What does P0442 mean?

P0442: Evaporative Emission System Leak Detected (Small Leak). The EVAP leak test found a small leak (about 1 mm or more).

What are the symptoms of P0442?

Check engine light. Possibly a fuel smell. Usually no change in how the car drives.

What causes P0442?

Loose or worn fuel cap seal. Cracked EVAP hose. Leaking canister or vent valve. Leaking filler neck.

How do you diagnose P0442?

1. Check and replace the fuel cap seal if worn 2. Smoke-test the system with the vent valve closed 3. Inspect hoses near the tank and the canister

Can I drive with P0442?

Usually yes. P0442 rarely affects how the car drives, but it keeps the check engine light on and can fail an emissions test.