Diagnosing P0455 on Your 2024 Subaru Outback
A P0455 on your 2024 Outback means the ECM detected a large EVAP leak. Your 6th-generation Outback with the 2.5L boxer or 2.4L turbo is fully under Subaru's warranty. The gas cap is the most common cause.
Symptoms
- Check engine light with P0455
- Possible faint fuel smell
- Gas cap not clicking
- EVAP monitor incomplete
Most Likely Causes
- Gas Cap (Very High Likelihood): Loose or not seated. Tighten until it clicks.
- Software Calibration (Medium Likelihood): ECM may need Subaru TSB update.
- Purge Control Solenoid (Medium Likelihood): Subaru's purge valve. Warranty replacement.
- Vent Control Valve (Low Likelihood): Stuck open. Warranty-covered.
- EVAP Line Connection (Low Likelihood): Assembly issue. Warranty-covered.
What to Do
Tighten the gas cap and drive 2–3 days. If P0455 persists, visit a Subaru dealer for free diagnostics and repair.
Warranty Coverage
Your 2024 Outback is covered by Subaru's 3-year/36,000-mile basic warranty through 2027 and the federal emissions warranty (8yr/80k) through 2032.
Safe to Drive?
Yes. P0455 doesn't affect the Outback's boxer engine, CVT, or Symmetrical AWD.