Cracking P0455 on Your 2017 Honda Accord
A P0455 on your 2017 Honda Accord indicates a large EVAP system leak. As the final year of the 9th-generation Accord, your vehicle is out of basic warranty but may have remaining federal emissions coverage. The gas cap is the most likely culprit and the cheapest fix.
Clues Present
- Check engine light with P0455
- Possible fuel odor near the rear
- Worn or cracked gas cap seal
- Emissions test failure
Suspects Ranked
- Gas Cap Seal (Very High Likelihood): After 7–8 years the seal degrades. $10–$25 for an OEM replacement. Fixes most P0455 cases.
- Canister Vent Shut Valve (Medium Likelihood): Age-related valve failure. $150–$250 installed.
- EVAP Hose Deterioration (Medium Likelihood): Rubber lines crack with years of heat cycling. $80–$200.
- Bypass Solenoid Valve (Low Likelihood): Honda EVAP component. $120–$220.
- Charcoal Canister (Low Likelihood): Saturated or cracked. $200–$350.
DIY Diagnostic Path
Replace the gas cap first—cheapest and most likely fix. Clear the code with an OBD-II scanner. If P0455 returns after 2–3 drive cycles, inspect EVAP hoses visually. The canister vent shut valve is near the charcoal canister by the fuel tank. For hidden leaks, a smoke test ($100–$150 at a shop) is the definitive diagnostic.
Warranty Window
Honda's basic warranty has long expired. The federal emissions warranty (8 years/80,000 miles) covers through 2025—you're in the final window. Call your Honda dealer immediately to check if you still qualify for free EVAP repair.
Costs
Gas cap: $10–$25. Vent shut valve: $150–$250 shop, $60–$90 DIY parts. EVAP hose: $80–$200. Smoke test: $100–$150. Highly DIY-friendly for most causes.
Safe to Drive?
Yes. P0455 doesn't affect your 9th-gen Accord's 2.4L or 3.5L V6 engine performance.