Tracking P0456 on Your 2022 Outback
Your 2022 Outback (6th generation) has triggered P0456—a very small EVAP leak. The 2.5L Boxer four-cylinder (or 2.4L turbo XT) with Symmetrical AWD uses a traditional threaded gas cap and standard EVAP system. Subaru's 3yr/36k warranty runs through 2025—check if you still have time.
Evidence
- Check engine light on
- P0456 stored
- No performance issues
- Gas cap may show wear after 3+ years
Suspects
- Gas Cap Seal (High Likelihood): Three years of wear on the threaded cap. $0 warranty or $10–$15.
- Purge Control Solenoid Valve (High Likelihood): Known Subaru weak point—multiple TSBs exist. $0 warranty or $90–$210.
- Canister Vent Valve (Medium Likelihood): Vent control. $0 warranty or $100–$230.
- EVAP Hose (Medium Likelihood): Under-body connection. $110–$240.
- Charcoal Canister (Low Likelihood): Fuel overfilling damage. $200–$380.
Diagnostic Steps
- Reseat or replace gas cap ($10–$15 at dealer or auto parts store)
- Check warranty—Subaru 3yr/36k runs through 2025
- If covered, dealer appointment—ask about EVAP TSBs
- If out of warranty, clear code, drive cycle, smoke test if persistent
Costs
- Under warranty: $0
- Gas cap: $10–$15
- Purge valve: $90–$210
- Canister vent valve: $100–$230
Can I Drive?
Yes. P0456 has zero impact on the Boxer engine, AWD, or safety systems.
Warranty
Subaru's 3yr/36k through 2025—check mileage. 5yr/60k powertrain. Federal emissions 8yr/80k covers EVAP through 2030. Check for applicable TSBs even if basic warranty expired.