Solving P0455 on Your 2023 Toyota Prius
A P0455 on your 2023 Toyota Prius means the ECM detected a large EVAP system leak. Your all-new 5th-generation Prius on the TNGA-C platform with the 2.0L hybrid powertrain is under full warranty. Even with the redesign, the Prius still has a gasoline engine and EVAP system. Check the gas cap first.
Symptoms
- Check engine light with P0455
- Possible faint fuel odor
- Gas cap not clicking
- EVAP readiness monitor incomplete
Top Causes
- Gas Cap Seal (Very High Likelihood): Loose or defective. Tighten until it clicks. Warranty-covered.
- Canister Close Valve (CCV) (Medium Likelihood): Toyota's vent valve. Warranty-covered.
- EVAP Hose Connection (Medium Likelihood): New platform assembly issue. Warranty-covered.
- Purge VSV (Low Likelihood): Vacuum switching valve. Warranty-covered.
- ECU Software (Low Likelihood): First-year software calibration. Free reflash.
What to Do
Tighten the gas cap and drive 2–3 days. If the light persists, your Toyota dealer handles everything under warranty.
Warranty Coverage
Your 2023 Prius is covered by Toyota's 3-year/36,000-mile basic warranty (through 2026), 5-year/60,000-mile powertrain warranty, and federal emissions warranty (8yr/80k). All EVAP repairs are free.
Safe to Drive?
Yes. P0455 doesn't affect the Prius's 2.0L hybrid powertrain, EV mode, or fuel economy.