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Home >> GMC >> 1999 >> Forward Control 6.5 F, Standard >> Repair and Diagnosis >> External Pages >> Different car >> Section 249 (Engine Controls - Removal & Installation) >> Emission Systems & Sub-Systems >> EVAP System Cleaning >> Inspection Procedure
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Inspection Procedure

WARNING: This page is about a different car, the 2003 Pontiac Bonneville, 2003 Buick Park Avenue, and 2003 Buick LeSabre. However, it is still accessible from the selected car via links, so may be relevant.
  1. Turn OFF the ignition off. Remove the EVAP canister purge solenoid. See EVAP CANISTER PURGE SOLENOID  under MOTORS & SOLENOIDS. Lightly tap the EVAP canister purge solenoid on a hard surface.
  2. 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.
  3. 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 solenoid. Return to the diagnostic procedure that sent you here.