Power Steering System Test Procedure

The Power Steering System Test Procedure will test the operation of the hydraulic power steering, test the operation of the power steering pump and power steering gear and identify restrictions in the system.

1. Turn the ignition switch to the OFF position. Place a drain pan under the vehicle in order to catch any power steering fluid. Disconnect the power steering pressure pipe/hose from the power steering pump or the power steering gear as necessary. Install the Power Steering System Analyzer (J-44721) between the power steering pump and the power steering gear on the pressure side. Adapters may be required. Inspect and add ONLY approved power steering fluid as necessary in order to ensure that the power steering fluid is at the proper level and not contaminated. Is the fluid at the proper level and free from contamination? If yes, go to step  3 . If no, go to next step.
2. Fill or drain and refill the fluid as necessary. Is the fluid at the proper level and free from contamination? If yes, go to next step.
NOTE: DO NOT hold the steering wheel in the full turn position longer than 5 seconds, as damage to the steering pump may result.
3. Fully open the Power Steering System Analyzer valve. Start the engine. Turn the steering wheel and BRIEFLY hold the steering wheel against the steering stop in order to release any trapped air from the system. Inspect and ensure that all of the power steering pipe/hose connections are not leaking. Observe the pressure reading. Is the pressure reading greater than 230 psi (1379 kPa)? If yes, go to next step. If no, go to step  5 .
CAUTION: A restriction may be present in the power steering system. Turn off the engine IMMEDIATELY.
4. Locate and repair the restriction. Did you complete the repair? If yes, go to step  16 .
5. Inspect and add ONLY approved power steering fluid as necessary in order to ensure that the power steering fluid is at the proper level. Allow the engine to run until the engine reaches full operating temperature. Record the pressure reading and flow reading (A). Partially close the Power Steering System Analyzer valve until the system pressure reaches 700 psi (4827 kPa), then record the FLOW reading (B). Subtract flow reading B from flow reading A. Is the flow DECREASE greater than 3.8 L (1 gal) per minute? If yes, go to step  11 . If no, go to next step.
NOTE: DO NOT leave the valve fully closed for more than 5 seconds, or the pump could be damaged internally.
6. Fully close then open the Power Steering System Analyzer valve 3 times. Record all of the high pressure readings. Are the three high pressure readings within specifications? See POWER STEERING PUMP SPECIFICATIONS  . If yes, go to next step. If no, go to step  13 .
7. Are the three high pressure readings within 245 kPa (50 psi) of each other? If yes, go to next step. If no, go to step  12 .
8. Increase the engine speed to approximately 1500 RPM. Record the flow reading. See POWER STEERING PUMP SPECIFICATIONS  . Is the actual flow reading within specifications? If yes, go to next step. If no, go to step  11 .
9. Is the difference between the actual flow reading and the maximum flow specification more than 3.8 L (1 gal) per minute? If yes, go to step  14 .
NOTE: DO NOT hold the steering wheel in the full turn position longer than 5 seconds, as damage to the steering pump may result.
10. Turn the steering wheel from steering stop to steering stop and record the FLOW readings at each stop. Is the flow LOWER than 3.8 L (1 gal) per minute? If yes, go to step  17 . If no, go to step  15 .
11. Replace the power steering pump. See POWER STEERING PUMP  under REMOVAL & INSTALLATION. Did you complete the replacement? If yes, go to step  16 .
12. Remove the power steering pump flow control valve. If any burrs or scratches are noticed on the flow control valve, replace the flow control valve. See POWER STEERING PUMP FLOW CONTROL VALVE REPLACEMENT  under REMOVAL & INSTALLATION. Do NOT attempt to clean the flow control valve. Inspect the flow control valve bore. If any burrs or scratches are present in the control valve bore, replace the power steering pump. See POWER STEERING PUMP  under REMOVAL & INSTALLATION. Did you complete the repair? If yes, go to step  16 .
13. Replace the power steering pump flow control valve. See POWER STEERING PUMP FLOW CONTROL VALVE REPLACEMENT  under REMOVAL & INSTALLATION. Did you complete the replacement? If yes, go to step  16 .
14. DO NOT disassemble the flow control valve. Remove the power steering pump flow control valve and inspect for any wear or damage. If the flow control valve is worn damaged, replace the flow control valve. Did you complete the repair? If yes, go to step  16 .
15. The power steering gear is leaking across the piston or bypassing the valve circuit. Replace the power steering gear. See STEERING GEAR  under REMOVAL & INSTALLATION. Did you complete the replacement? If yes, go to step  16 .
16. Test the power steering system for the original condition. Does the original condition still exist? If yes, go to step  1 . If no, go to next step.
17. Disconnect and remove the Power Steering System Analyzer from the vehicle. Connect the vehicle power steering pipes/hoses. Bleed the power steering system and add fluid as necessary.