P0455 on Honda
Evaporative Emission Control System Leak Detected (Gross Leak)
P0455 on Honda vehicles indicates evaporative emission control system leak detected (gross leak). Au7o has documented this code across 4 Honda models — most commonly on Accord, Civic, CR-V. This code means your car's evaporative emission (EVAP) system has detected a large (gross) leak, so fuel vapors that should be sealed inside the fuel and vapor system are escaping into the atmosphere. The EVAP system captures gasoline vapors from the tank and routes them to the engine to be burned instead of polluting the air, and the computer periodically pressure- or vacuum-tests this sealed system. A gross leak almost always points to something obvious and easy, like a loose, missing, or bad gas cap, rather than a deep mechanical failure. It rarely affects how the car drives, but it should be fixed to pass emissions and stop wasting fuel vapor. Typical repair costs on Honda range from $20 to $500, depending on the specific model and root cause.
Common Causes of P0455
- •Loose, missing, or improperly tightened gas cap
- •Worn, cracked, or failed gas cap seal
- •Cracked or disconnected EVAP/vapor hose
- •Damaged or missing fuel filler neck seal
- •Faulty EVAP purge valve stuck open
- •Failed EVAP vent valve
- •Cracked or damaged charcoal canister
P0455 on Honda by Model
Honda Accord(1 issue)
- EVAP Canister Purge Valve Sticking - P0455 / P0496 / P04412008-2015
The EVAP canister purge control solenoid on the intake manifold sticks open, throwing evaporative-system codes — commonly P0496 (EVAP flow during a non-purge condition), P0441 (incorrect purge flow), or a large-leak P0455 — and causing rough idle, hard/rough starts right after refueling, and a faint fuel smell. A worn or non-OEM gas cap is the first thing to rule out for P0455; if a genuine cap doesn't clear it, the purge valve is the usual culprit. The under-car vent solenoid at the charcoal canister is a secondary leak source from corrosion.
Honda Civic(1 issue)
- P0455 — Gross EVAP Leak from a Failed Gas Cap or Stuck-Open Purge/Vent Valve2006-2024
P0455 indicates a large (gross) leak in the evaporative emission system — the PCM cannot build or hold EVAP vacuum/pressure at all. On the Honda Civic the two most frequent causes are strikingly simple: a gas cap that no longer seals (missing, loose, or a badly degraded O-ring) and the canister purge solenoid valve sticking open. On the 8th-gen (2006-2011) Civic the purge valve is mounted right on the intake manifold and a stuck-open valve is a documented failure. A stuck canister vent valve is another common source and can also cause a symptom drivers notice — difficulty pumping fuel / the pump clicking off early. On 10th- and 11th-gen (2016+, and especially capless-fill 2022+) Civics, the capless filler not fully closing after fueling has triggered P0455/P0456 EVAP leak codes.
Honda CR-V(1 issue)
- P0455 — Gross EVAP Leak from Bad Gas Cap Seal, Filler Neck, or Stuck Vent Valve2002-2020
P0455 is the large/gross EVAP leak code on the CR-V and points to a big open path in the fuel-vapor system. The most frequent CR-V causes are a missing, cross-threaded, or aftermarket gas cap that will not hold vacuum; a corroded or damaged fuel filler neck/main flap where the cap seals (a rust-belt problem on older Gen2/Gen3 CR-Vs); and the canister vent solenoid at the rear of the vehicle, which sits near the charcoal canister and is exposed to road salt and debris so it sticks open and never seals during the self-test. Cracked or disconnected EVAP hoses to the canister can also throw it.
Honda Pilot(1 issue)
- EVAP Canister Purge Valve Stuck Open (P0496/P0455) Causing Hard Start After Refueling2016-2022
The EVAP canister purge valve sticks open and allows fuel vapors to flow into the intake when they shouldn't. On 3rd-gen Pilots this commonly sets P0496 (EVAP high/incorrect purge flow), and can accompany P0455/P0441; drivers notice a check engine light, rough idle, and pronounced difficulty starting the engine immediately after filling up (flooded intake). The canonical OEM purge valve for these years is 36162-5G0-A01.
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View P0455 across all makes →Frequently Asked Questions
What does P0455 mean on Honda?▼
P0455 stands for "Evaporative Emission Control System Leak Detected (Gross Leak)." This code means your car's evaporative emission (EVAP) system has detected a large (gross) leak, so fuel vapors that should be sealed inside the fuel and vapor system are escaping into the atmosphere. The EVAP system captures gasoline vapors from the tank and routes them to the engine to be burned instead of polluting the air, and the computer periodically pressure- or vacuum-tests this sealed system. A gross leak almost always points to something obvious and easy, like a loose, missing, or bad gas cap, rather than a deep mechanical failure. It rarely affects how the car drives, but it should be fixed to pass emissions and stop wasting fuel vapor. On Honda specifically, this code is documented across 4 models.
What causes P0455 on Honda vehicles?▼
Common causes on Honda: Loose, missing, or improperly tightened gas cap, Worn, cracked, or failed gas cap seal, Cracked or disconnected EVAP/vapor hose, Damaged or missing fuel filler neck seal, Faulty EVAP purge valve stuck open. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P0455 on a Honda?▼
Repair costs on Honda range from $20 to $500, depending on the specific model and root cause.
Which Honda models have P0455 documented?▼
Au7o has documented P0455 on 4 Honda models: Accord, Civic, CR-V, Pilot.