P0455 on Jeep
Evaporative Emission Control System Leak Detected (Gross Leak)
P0455 on Jeep vehicles indicates evaporative emission control system leak detected (gross leak). Au7o has documented this code across 2 Jeep models — most commonly on Grand Cherokee, Wrangler. 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 Jeep range from $25 to $450, 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 Jeep by Model
Jeep Grand Cherokee(1 issue)
- 2015 P0455/P0456 From a Split Purge Hose - TSB 25-002-15 Rev. A2015
FCA TSB 25-002-15 Rev. A covers a narrow population of 2015 WK Grand Cherokee vehicles built on or after November 16, 2014 and on or before January 17, 2015. On a covered vehicle with P0455 and/or P0456, a split evaporative-emissions purge-valve hose can prevent the system from sealing. The bulletin specifies 68189075AE for the 3.6L ERB engine and 68189065AD for the 5.7L EZH engine. It does not support the old card's blanket 2005-2021 claim that these codes are an ESIM failure.
Jeep Wrangler(1 issue)
- EVAP Leak Detection Pump / ESIM Module Failure Triggers P0455, P0456 & P0457 (Often Misdiagnosed as Gas Cap)2007-2018
The JK-generation Jeep Wrangler uses Chrysler's Natural Vacuum Leak Detection (NVLD) approach for its evaporative emissions (EVAP) system, implemented through a leak detection device commonly called the ESIM (Evaporative System Integrity Module) or leak detection pump (LDP). Rather than an active vacuum pump, this module monitors natural temperature-induced pressure/vacuum changes in the fuel/EVAP system to confirm the system is sealed. The ESIM is a known, high-frequency failure point: its internal diaphragm/seal hardens or cracks (or the housing cracks), causing the ECM to falsely detect an EVAP leak even when the system is actually sealed. The result is a check-engine light and one of several EVAP leak codes. Because the very first thing the code points the owner toward is the fuel cap, this failure is routinely misdiagnosed: owners (and shops) replace the gas cap one or more times, the light returns, and the actual culprit is the cheap ESIM/leak-detection module bolted to the charcoal canister. The module is a small white rectangular unit that twists/mounts onto the EVAP charcoal canister, located beneath the vehicle near the fuel tank / just ahead of the rear axle (driver side on most JKs). It is non-safety, non-drivability affecting, but it will cause a persistent CEL and an emissions/smog-test failure. This affects the 3.8L V6 (2007-2011) and 3.6L Pentastar (2012-2018) JK Wranglers, including 2-door and Unlimited 4-door.
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View P0455 across all makes →Frequently Asked Questions
What does P0455 mean on Jeep?▼
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 Jeep specifically, this code is documented across 2 models.
What causes P0455 on Jeep vehicles?▼
Common causes on Jeep: 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 Jeep?▼
Repair costs on Jeep range from $25 to $450, depending on the specific model and root cause.
Which Jeep models have P0455 documented?▼
Au7o has documented P0455 on 2 Jeep models: Grand Cherokee, Wrangler.