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Pinpoint Test A: Steering Has Lack Of Assist Or Inconsistent Assist

  1. A1 CHECK FOR POWER STEERING FLUID CONTAMINATION 
    • Check the power steering fluid for contamination.
    • Is the power steering fluid contaminated? 
    • Yes:  FLUSH the power steering system. REFER to POWER STEERING SYSTEM FLUSHING . CHECK the system for normal operation. If assist concern still exists, GO to A2  .
    • No:  GO to A2  .
  2. A2 CHECK THE STEERING ASSIST WITH THE ENGINE RPM RAISED 
      NOTE: Do not hold the steering wheel at the stops for an extended amount of time. Damage to the power steering pump may occur.
    • Set the engine at 2,100 RPM and turn the steering wheel fully to the left and right.
    • Is steering assist fully restored to normal with the engine RPM raised? 
    • Yes:  INSTALL a new power steering pump. REFER to POWER STEERING .
    • No:  GO to A3  .
  3. A3 CHECK FOR A CHANGE OF ASSIST ON LEFT AND RIGHT TURNS 
    • With the engine at idle, turn the steering wheel fully to the left and to the right.
    • Does the steering assist change when turning from right to left? 
    • Yes:  INSTALL a new steering gear. REFER to POWER STEERING .
    • No:  GO to A4  .
  4. A4 CHECK THE STEERING LINES AND HOSES FOR RESTRICTIONS 
    • Inspect the steering lines and hoses for damage, kinks or restrictions.
    • Are the steering lines or hoses damaged, kinked or restricted? 
    • Yes:  INSTALL new lines or hoses as necessary.
    • No:  GO to A5  .
  5. A5 MONITOR THE ENGINE RPM CHANGES 
    NOTE: Do not hold the steering wheel at the stops for an extended amount of time. Damage to the power steering pump may occur.
    NOTE: Make sure that the vehicle is on a flat dry surface, all accessories are in the OFF position and that the steering system is at normal operating temperature.
    • Connect the scan tool.
    • Start the engine.
    • With the engine at idle, raise the power steering fluid temperature to 74-80°C (165-176°F) by rotating the steering wheel fully to the left and right several times.
    • Enter the following diagnostic mode on the scan tool: DataLogger - PCM.
    • Monitor the Engine Revolutions Per Minute (RPM) PID while turning the steering wheel quickly to the left stop position and then to the right stop position.
    • Note the engine RPM during the turns.
    • Does the engine RPM change (even temporarily) more than 30 RPM when turning the steering wheel? 
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