Evaporative Emissions System: Service and Repair

Evaporative Emission System Cleaning

Tools Required

J 41413 EVAP Pressure/Purge Diagnostic Station

Inspection Procedure

Caution: Refer to Fuel and Evaporative Emission Pipe Caution Fuel and Evaporative Emission Pipe Caution in Cautions and Notices.

Important: Proceed with the following procedure only when performing a purge valve replacement.


1. Turn OFF the ignition.
2. Remove the evaporative emission (EVAP) canister purge valve. Refer to Evaporative Emission Canister Purge Solenoid Valve Replacement Service and Repair.
3. Lightly tap the EVAP canister purge valve on a hard surface.
4. Inspect for carbon particles exiting either of the vacuum ports.

* If contamination is found during the inspection procedure. Replace the EVAP canister purge valve and continue with the cleaning procedure.
* If no contamination is found, continue with the published service procedure.

Cleaning Procedure

1. Connect the J 41413 .
2. Raise the vehicle. Refer to Lifting and Jacking the Vehicle Service and Repair in General Information.
3. Remove the EVAP canister. Refer to Evaporative Emission Canister Replacement Service and Repair.
4. Turn OFF the main valve on the J 41413 .
5. Disconnect the hose from the diagnostic station pressure regulator.
6. Using a section of vacuum hose, connect one end onto the diagnostic station pressure regulator.
7. Connect the other end of the vacuum hose to the canister side of the purge pipe.
8. Turn ON the main nitrogen cylinder valve and continue to discharge nitrogen for 15 seconds.
9. If the nitrogen does not dislodge the carbon particles, replace the purge pipe. Refer to Evaporative Emission Hoses/Pipes Replacement - Engine/Chassis Evaporative Emission Hoses/Pipes Replacement - Engine/Chassis.
10. Return the J 41413 to its original condition.

Important: The EVAP canister must be replaced if contamination is found.


11. Install a new EVAP canister. Refer to Evaporative Emission Canister Replacement Service and Repair.
12. Lower the vehicle.
13. Install a new EVAP canister purge valve. Refer to Evaporative Emission Canister Purge Solenoid Valve Replacement Service and Repair.