Solving P0455 on Your 2020 Subaru Outback
A P0455 on your 2020 Outback means the ECM detected a large EVAP leak. Your 6th-generation Outback with the 2.5L or 2.4L turbo is out of Subaru's basic warranty but covered by the emissions warranty. Start with the gas cap.
Symptoms
- Check engine light with P0455
- Faint fuel odor
- Gas cap seal worn after 5+ years
- Failed emissions test
Causes by Probability
- Gas Cap Seal (Very High Likelihood): Worn seal. Replace for $10–$25.
- Purge Control Solenoid (Medium Likelihood): Subaru's purge valve. $100–$200.
- Vent Control Valve (Medium Likelihood): Stuck open. $120–$220.
- Vapor Line (Low Likelihood): Cracked hose. $80–$200.
- Charcoal Canister (Low Likelihood): Saturated. $200–$350.
What to Do
Replace the gas cap ($10–$25), clear the code, drive 2–3 cycles. If P0455 returns, get a smoke test.
Warranty Coverage
Subaru's basic warranty (3yr/36k) has expired. The federal emissions warranty (8yr/80k) covers EVAP through 2028.
Safe to Drive?
Yes. P0455 doesn't affect the Outback's boxer engine, CVT, or Symmetrical AWD.