P0455 Investigation on Your 2021 Subaru Crosstrek
Your 2021 Crosstrek's ECM has detected a large EVAP leak—that's what P0455 means. The 2.0L or 2.5L boxer engine runs fine, but this vapor leak code needs resolution. The gas cap is clue #1.
What You'll Notice
- Check engine light on
- P0455 stored in ECM
- Possible fuel odor
- Gas cap not seating correctly
Ranked Causes
- Gas Cap Seal (Very High Likelihood): The simplest fix. $10–$25.
- Purge Control Solenoid (Medium Likelihood): Sticking valve on the intake. $150–$280 installed.
- Vent Control Valve (Medium Likelihood): Near the charcoal canister. $120–$250 installed.
- Vapor Hose (Low Likelihood): Cracked from heat cycling. $80–$200.
- Charcoal Canister (Low Likelihood): Saturated. $200–$400 installed.
What to Do
Replace the gas cap first—it's the cheapest test. If P0455 returns, get a smoke test. Subaru dealers use SSM4 for precise EVAP diagnostics.
Warranty Status
Your 2021 Crosstrek's basic warranty (3yr/36k) has likely expired. The federal emissions warranty (8yr/80k) covers EVAP components through 2029. Verify mileage with your dealer.
Safe to Drive?
Yes. P0455 is a vapor code only. The boxer engine, CVT, Symmetrical AWD, and EyeSight work normally.