LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Cadillac >> 2006 >> STS V >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control System - 4.4L - Troubleshooting & Diagnosis >> Boost Control System Diagnosis >> Circuit/System Testing
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Circuit/System Testing

  1. Ignition OFF, disconnect the boost source hose from the boost control solenoid, connect the J 35555  to the boost source hose.
  2. Engine running, observe the gage on the J 35555  for a reading equal to or greater then 15 inch Hg.
    • If less than 15 inch Hg, repair the boost vacuum source hose or the intake manifold port for a restriction or blockage.
  3. Ignition OFF, connect the vacuum source hose to the boost solenoid.
  4. Disconnect the boost signal hose from the bottom port of the bypass valve actuator and connect the J 35555  to the boost signal hose.
  5. Engine running, observe the gage on the J 35555  for a reading of 0-1 inch Hg.
    • If greater than the specified range, replace the boost control solenoid.
  6. Engine running, command the boost control solenoid to 0% DC with a scan tool. Observe the gage on the J 35555  for a reading equal to or greater than 15 inch Hg.
    • If less than the specified range, test the boost signal hose for a restriction or blockage. If the boost signal hose tests normal, replace the boost control solenoid.
  7. Disconnect the inlet vacuum signal hose from the top of the bypass valve actuator, and connect J 35555  to the inlet vacuum signal hose.
  8. Engine running, observe the gage on the J 35555  for a reading equal to or greater than 15 inch Hg.
    • If less than 15 inch Hg, repair the inlet vacuum signal hose or the intake manifold port for a restriction or blockage.