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Circuit/System Testing

IMPORTANT: You must perform the Circuit System Verification before proceeding with Circuit/System Testing.
  1. Disconnect the inlet vacuum signal hose from the bypass valve actuator.
  2. Connect a vacuum gage to the inlet vacuum signal hose.
  3. Engine running, observe the vacuum gage. The reading should be more than 15 in Hg.
  4. Disconnect the boost signal hose from the bypass valve actuator.
  5. Connect a vacuum gage to the boost signal hose.
  6. Start and idle the engine in Park. Observe the vacuum gage. The reading should be 0 in Hg.
  7. Ignition OFF, connect the J 35555  to the inlet vacuum signal port on the bypass valve actuator. Slowly apply vacuum to the valve while observing the bypass actuator. The bypass actuator rod should retract.
    • If the bypass actuator rod does not retract, disconnect the actuator from the bypass cable and apply vacuum to the actuator. If the actuator still does not retract, replace the actuator.
    • If the actuator valve retracts after disconnecting the bypass cable, remove the supercharger and throttle body. Inspect the bypass cable and valve for a binding condition or a disconnected bypass valve. Refer to Supercharger Cleaning and Inspection .
    8. CAUTION: Refer to Road Test Caution .
  8. Engine running, on a road test take a snapshot of the induction data list while depressing the accelerator pedal to WOT, then releasing the throttle to the at rest position. Exit from the snapshot and review the data. Refer to Scan Tool Snapshot Procedure . The MAP sensor parameter on the scan tool should increase rapidly. This increase should be from approximately 35 kPa at idle to more than 130 kPa.
    • If the MAP sensor parameter does not increase, remove the supercharger and throttle body. Inspect the bypass cable and brackets for the following conditions:
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