P0455 — EVAP Large or Gross Leak Detected

P0455 is set when the EVAP system's gross-leak monitor detects an opening approximately 0.090 inches (2.3 mm) or larger — or in many cases, no seal at all. This is the size of a missing gas cap, a disconnected hose, or a failed vent solenoid stuck open. The system cannot hold pressure or vacuum for the calibration period, so the ECM concludes a major leak.

Severity: low powertrain Safe to drive (short term)

Pick your vehicle for a P0455 diagnosis

Select your exact year, make, and model below to get a diagnostic guide tuned to your vehicle's known failure patterns and TSBs.

2010-2014

2015-2019

2020-2024