Fuel and Emissions System Description - EVAP System

Fuel and Emissions System Description - EVAP System

Evaporative Emission (EVAP) Control System

Refer to the system diagram to see a functional layout of the system.

EVAP Canister

The EVAP canister temporarily stores fuel vapor from the fuel tank until it can be purged back into the engine and burned.

EVAP Canister Purge Valve

When the engine coolant temperature is below 140 °F (60 °C), the ECM turns off the EVAP canister purge valve which cuts vacuum to the EVAP canister.






Fuel Tank Pressure (FTP) Sensor

The FTP sensor converts fuel tank absolute pressure into an electrical input to the ECM.






EVAP Canister Vent Shut Valve

The EVAP canister vent shut valve is on the EVAP canister.

The EVAP canister vent shut valve controls the venting of the EVAP canister.






Evaporative Emission (EVAP) Control Diagram

The EVAP controls minimize the amount of fuel vapor escaping into the atmosphere. Vapor from the fuel tank is temporarily stored in the EVAP canister until it can be purged from the canister into the engine and burned.

The EVAP canister is purged by drawing fresh air through it and into a port on the intake manifold.

The purging vacuum is controlled by the EVAP canister purge valve, which operates whenever engine coolant temperature is above 140 °F (60 °C).






Fuel Cap Warning Message

The ECM detects a loose or missing fuel fill cap as an evaporative system leak, and alerts the driver by showing a warning message in the gauge display.

First drive cycle

The first time a leak is detected, a CHECK FUEL CAP message is shown in the gauge display (A). To scroll to another message, press the select/reset button. The CHECK FUEL CAP message appears each time you restart the engine until the system turns the message off. Turn the engine off, then replace or tighten the fuel fill cap until clicks at least once.






To make the message go off (with the HDS)

Procedure

1. Tighten the fuel fill cap until it clicks.

2. Clear the Pending DTC with the HDS.

3. Verify there is no leak by doing the EVAP FUNCTION TEST in the INSPECTION MENU with the HDS.

To make the message go off (without the HDS) ('06 model)

Procedure

4. Tighten the fuel fill cap until it clicks.

5. The message should go off after several days of normal driving.

To make the message go off (without the HDS) ('07-10 models)

Procedure

6. Tighten the fuel fill cap until it clicks.

7. Start the engine, then turn the ignition switch to LOCK (0).

8. Repeat step 7 two more times.