For 1990-2009 cars

Problem | Action
--- | ---
There is a stuck or inoperative flow control valve | Replace or clean the valve.
The pressure plate is not flat against the cam ring | Replace the pressure plate.
There is extreme wear of the cam ring |

1. Replace the cam ring.
2. Flush the system. Refer to Power Steering System Flushing .

There is a scored pressure plate, thrust plate, or rotor |

1. Replace any scored parts.

If the rotor is scored, replace the rotor with a rotating group.

2. Flush the system.

Refer to Power Steering System Flushing .

The vanes are sticking in the rotor slots. | Free the vanes by removing any burrs, varnish or dirt.
There is improper installation of the vanes | Properly install the vanes. Ensure that you install the radius edge to the outside.
There is air in the fluid | Locate and repair the leak.
There is low power steering fluid | Add the necessary amount of power steering fluid. Refer to Checking and Adding Power Steering Fluid .
The pump belt is slipping. | Refer to Drive Belt Replacement in Engine Mechanical - 2.4L or Drive Belt Replacement in Engine Mechanical - 3.4L.
There are damaged hoses or steering gear | Replace any damaged parts.