LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Geo >> 1991 >> Storm GSi, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - System/Component Tests >> Air Induction Systems >> SECONDARY AIR CONTROL (GSi)
April 5, 2026: LEMON Manuals is launched! Read the announcement.

SECONDARY AIR CONTROL (GSi)

  1. Disconnect vacuum supply hose from secondary air control (intake air) Vacuum Switching Valve (VSV), located at rear of engine compartment. The VSV contains a White/Blue and Black/Yellow wire connector. Using vacuum gauge, check vacuum reading at supply hose with engine idling.
  2. Vacuum reading should be 10 in. Hg. If reading is not correct, repair vacuum leak. If reading is okay, connect vacuum pump to vacuum supply side of VSV.
  3. With ignition on and engine off, apply vacuum and note linkage operation at vacuum actuator for auxiliary valves.
  4. If linkage moves, proceed to step 7). If linkage does not move, disconnect electrical connector at VSV and repeat step 3). If linkage moves with electrical connector removed, check for short to ground in White/Blue wire from ECM to VSV or faulty ECM. The ECM is located under left side of instrument panel, left of steering column.
    CAUTION: Automatic transaxle Electronic Control Unit (ECU) on 4-speed transaxle may be mounted on left side of steering column. DO NOT confuse this with the ECM. The ECM contains 24-pin and 32-pin connectors, and the ECU contains 16-pin and 20-pin connectors.
  5. If linkage does not move, disconnect vacuum hose at vacuum actuator. Install vacuum gauge and note vacuum reading with engine running. Vacuum reading should be at least 10 in. Hg.
  6. If vacuum reading is not correct, VSV is defective. If vacuum reading is correct, check for binding linkage or defective actuator.
  7. Install jumper wire between terminals No. 1 and 3 of ALDL connector, located behind right side of instrument panel, near kick panel. See Fig 1. Apply vacuum and note linkage movement. If linkage does not move, secondary air control system is okay. If linkage moves, proceed to step 8).
  8. Disconnect electrical connector from VSV. Turn ignition on with engine off. Ensure jumper wire is still installed in ALDL connector. Using test light, check for voltage between VSV electrical connector terminals.
  9. If voltage exists, VSV is defective. If no voltage exists between connector terminals, check for power between Black/Yellow wire of VSV electrical connector and ground.
  10. If no power exists, repair open circuit in Black/Yellow wire between VSV and 15-amp engine fuse in fuse block, located behind left kick panel. If power exists, check for open circuit in White/Blue wire between VSV and ECM, defective connections or defective ECM.
Fig 1: Identifying ALDL Terminals
G90D14939Courtesy of GENERAL MOTORS CORP.