P0455 on RAM
Evaporative Emission Control System Leak Detected (Gross Leak)
P0455 on RAM vehicles indicates evaporative emission control system leak detected (gross leak). Au7o has documented this code across 1 RAM model — most commonly on 1500. 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 RAM range from $30 to $300, 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 RAM by Model
RAM 1500(1 issue)
- P0456 / P0442 EVAP Small Leak — ESIM Pump and Purge Valve / Capless Filler Seal2013-2024
A very common check-engine complaint is EVAP 'small leak' codes P0456/P0442 (and sometimes P0455). On 2013-2020 trucks the usual culprits are the Evaporative System Integrity Monitor (ESIM) pump on the charcoal canister or a failed purge valve; on 2019+ capless-filler trucks the capless fuel-filler seal or the purge valve is the frequent cause. It won't harm the drivetrain but fails emissions testing and is a high-frequency search among owners.
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View P0455 across all makes →Frequently Asked Questions
What does P0455 mean on RAM?▼
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 RAM specifically, this code is documented across 1 model.
What causes P0455 on RAM vehicles?▼
Common causes on RAM: 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 RAM?▼
Repair costs on RAM range from $30 to $300, depending on the specific model and root cause.
Which RAM models have P0455 documented?▼
Au7o has documented P0455 on 1 RAM model: 1500.