GM Service Manual Online
For 1990-2009 cars only

Condition

Cause

Low Oil Pressure Due to Steering Pump

    â€¢ A stuck flow control valve
    â€¢ An inoperative flow control valve
    â€¢ The pressure plate not flat against the cam ring
    â€¢ Extreme wear of the cam ring
    â€¢ A scored pressure plate
    â€¢ A scored thrust plate
    â€¢ A scored rotor
    â€¢ The vanes sticking in the rotor slots
    â€¢ A cracked thrust plate
    â€¢ A cracked pressure plate
    â€¢ A broken thrust plate
    â€¢ A broken pressure plate
    â€¢ High internal leakage