P0455 on Acura
Evaporative Emission Control System Leak Detected (Gross Leak)
P0455 on Acura vehicles indicates evaporative emission control system leak detected (gross leak). Au7o has documented this code across 1 Acura model — most commonly on RDX. 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 Acura range from $40 to $150, 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 Acura by Model
Acura RDX(1 issue)
- Fuel Cap Gasket Fails to Seal Setting EVAP Large-Leak Codes P0455/P0456 (TSB 14-006)2012-2015
Second-generation RDX owners get a TIGHTEN FUEL CAP message and a check engine light for an EVAP leak, and the cap is tight. Acura issued service bulletin 14-006 covering the RDX and other Honda/Acura models: the original fuel cap's black gasket fails to seal reliably, so the EVAP system's leak monitor reports a leak that no amount of retightening will clear. Because the cap looks and feels fine, this is commonly chased with expensive smoke testing and purge-valve replacement before the cap is suspected. The EVAP fault will also block emissions-test readiness monitors.
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What does P0455 mean on Acura?▼
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 Acura specifically, this code is documented across 1 model.
What causes P0455 on Acura vehicles?▼
Common causes on Acura: 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 Acura?▼
Repair costs on Acura range from $40 to $150, depending on the specific model and root cause.
Which Acura models have P0455 documented?▼
Au7o has documented P0455 on 1 Acura model: RDX.