The P0455 is a quite common code because the code is set if the gas cap is loose or missing. Start by tightening the gas cap and clearing the code. In most cases, the code can be cleared by disconnecting the car battery for about 30 minutes.
Check the 'Possible Causes' listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.
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What is the Cost to Diagnose the Code?
Labor: 1.0
The cost to diagnose the P0455 Lexus code is 1.0 hour of labor. The diagnosis time and labor rates at auto repair shops vary depending on the location, make and model of the vehicle, and even the engine type. Most auto repair shops charge between $75 and $150 per hour.
What are Code Possible Symptoms?
Engine Light ON (or Service Engine Soon Warning Light)
What Does the P0455 Lexus Code Mean?
5 hours after the ignition switch is turned off, the leak detection pump creates negative pressure (vacuum) in the Evaporative Emission (EVAP) system. The Engine Control Module (ECM) monitors for leaks and actuator malfunctions based on the EVAP pressure. The leak detection pump creates negative pressure through the reference orifice. When the system is normal, the EVAP pressure is between 97 to 100 kPa(abs) [726 to 750 mmHg(abs) (Typical value)] and saturated within a minute. If the leak detection pump creates negative pressure (vacuum) in the EVAP system and the EVAP system pressure is measured. If the stabilized system pressure is higher than [second reference pressure x 0.2] (near atmospheric pressure), the ECM determines that the EVAP system has a large leak, illuminates the MIL, and stores the Diagnostic Trouble Code (DTC).
The Canister Pump Module is attached to the EVAP Canister and contains the Canister Pressure Sensor, the Leak Detection Pump, and the Vent Valve.
P0455 Lexus Code - Evaporative Emission Control System Gross Leak Detected