Evaporative Emission System Cleaning
Special Tools
GE-41413 Evaporative Emission System Tester (EEST)
For equivalent regional tools, refer to Special Tools .
Inspection Procedure
Caution: Use the EVAP Pressure/Purge Diagnostic Station CH 41413 in order to provide a clean, dry, low pressure gas source. Do not substitute any other pressurised gas source. Damage may result to the EVAP system.
Note: Proceed with the following procedure only if referenced by an evaporative emission (EVAP) diagnostic or repair procedure.
- Turn OFF the ignition.
- Remove the EVAP canister purge valve. Refer to Evaporative Emission Canister Replacement .
- Lightly tap the EVAP canister purge valve on a hard surface.
- 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
- Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .
- Remove the EVAP canister. Refer to Evaporative Emission Canister Replacement .
- Turn OFF the main valve on the GE-41413 tester .
- Disconnect the hose from the diagnostic station pressure regulator.
- Using a section of vacuum hose, connect one end onto the EVAP pressure/purge diagnostic station pressure regulator.
- Connect the other end of the vacuum hose to the canister side of the purge pipe.
- Turn ON the main nitrogen cylinder valve and continue to discharge nitrogen for 15 seconds.
- If the nitrogen does not clear the blockage, replace the purge pipe.
- Return the EVAP pressure/purge diagnostic station to the station's original condition.
- Install a new EVAP canister. Refer to Evaporative Emission Canister Replacement .
- Lower the vehicle.
- Install a new EVAP canister purge valve. Refer to Evaporative Emission Canister Purge Solenoid Valve Replacement .
- Return to the diagnostic table that sent you here.
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