Power Steering System: Diagnosis Cadillac STS I

Visual/Physical Inspection

1. Inspect for aftermarket devices which could affect the operation of the power steering system.
2. Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.
3. Inspect the power steering reservoir for the proper power steering fluid level and condition.

Symptoms List

Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom

1. «Power Steering Fluid Leaks»(ref-197600-S26432389512005101200000)
2. «Rattle, Clunk, or Shudder Noise from the Power Steering System»(ref-197600-S15129065962005101200000)
3. «Whine or Growl Noise from the Power Steering System»(ref-197600-S10827254172005101200000)
4. «Steering Effort Hard in One or Both Directions»(ref-197600-S24357985622005101200000)
5. «Steering Effort Too Easy in One or Both Directions»(ref-197600-S14499322352005101200000)

Scheme 1

Excessive Vacuum Drop Diagnosis

1. If the vacuum continues to drop, remove the pressure and return hose from the pump.
2. Install the plugs (1,2) supplied with the J 43485 into the pressure and return port. See «Special Tools»(ref-197600-S17841519732005101200000) .
3. Attach the J 43485 to the J 35555 or equivalent. See «Special Tools»(ref-197600-S17841519732005101200000) .
4. Place the J 43485 on or in the pump reservoir filler neck. See «Special Tools»(ref-197600-S17841519732005101200000) .
5. Apply a vacuum of 68 kPa (20 in Hg) maximum.
6. If the vacuum drops again, repair or replace the pump. If the vacuum holds steady, continue to check the other parts of the steering system.
7. Observe the fluid.
8. If condition persists, replace the following parts: The return hose clamps The return hose O-rings The pressure hose O-rings The gear cylinder line O-rings The reservoir to pump O-ring
9. Repeat the bleed procedure from the beginning.
10. Drive the vehicle approximately 16 km (10 mi) in order to warm the system to operating temperature. Evaluate vehicle on a smooth flat surface.
11. Verify the following conditions: There is smooth power assist. The vehicle operates quietly. The pump maintains the proper fluid level. There is not any leaking in the steering system. The fluid is free of foam or discoloration.