Investigating P0455 on Your 2019 Honda Accord
A P0455 on your 2019 Honda Accord means the ECM found a large EVAP system leak. Your 10th-generation Accord (CV platform) is out of Honda's basic warranty but well within the federal emissions warranty. The most common cause? A worn gas cap seal—a $15 fix.
Signs and Symptoms
- Check engine light with P0455 stored
- Fuel smell, especially after fill-ups
- Gas cap seal showing wear or cracking
- Failed emissions inspection
Ranked Causes
- Gas Cap Seal (Very High Likelihood): After 5–6 years, the rubber seal wears. Replace for $10–$25. Try this before anything else.
- Canister Vent Shut Valve (Medium Likelihood): Sticking open with age. $150–$250 for replacement.
- EVAP Hose Crack (Medium Likelihood): Heat-cycled rubber lines deteriorate. $80–$200.
- Bypass Solenoid Valve (Low Likelihood): Honda-specific EVAP valve. $120–$220.
- Fuel Sender Gasket (Low Likelihood): O-ring at the fuel pump module. $100–$250.
Diagnostic Approach
Replace the gas cap with an OEM Honda cap ($10–$25). Clear the code and drive 2–3 cycles. If P0455 returns, get a smoke test ($100–$150 at most shops). The smoke reveals exactly where vapor is escaping.
Warranty Coverage
Honda's basic warranty has expired. The federal emissions warranty (8 years/80,000 miles) covers EVAP components through 2027. Contact your Honda dealer to check mileage eligibility—this could be a free repair.
Repair Costs
Gas cap: $10–$25. Vent shut valve: $150–$250. Hose repair: $80–$200. Smoke test: $100–$150 (often waived with repair). Most owners pay under $250.
Safe to Drive?
Yes. P0455 doesn't affect engine performance or safety on your 1.5T or 2.0T Accord.