Emission Control Systems: Service and Repair

EVAPORATIVE EMISSION (EVAP) SYSTEM CLEANING

TOOLS REQUIRED
J 41413 EVAP Pressure/Purge Diagnostic Station

INSPECTION PROCEDURE

NOTE: Refer to Clean, Dry, Low Pressure Gas Source Notice in Service Precautions.

IMPORTANT: Proceed with the following procedure only if referenced by a EVAP diagnostic or repair procedure.

1. Remove the EVAP canister purge valve.
2. Lightly tap the EVAP canister purge valve on a hard surface.
3. Inspect for carbon particles exiting either of the vacuum ports.
^ If no carbon particles were detected, but a blockage was detected during a diagnostic procedure, install the original EVAP canister purge valve. Continue with the cleaning procedure.
^ If carbon particles are found during the inspection procedure, continue with the cleaning procedure.
^ If a diagnostic procedure directed you to replace the EVAP canister purge valve and no carbon particles were detected, replace the EVAP canister purge valve. Return to the published service procedure.

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