Component Tests and General Diagnostics

Fig. 1 Power Steering Pressure Gauge Connections:

SYSTEM PRESSURE TEST
NOTE: When performing system test procedures, power steering pressures can easily exceed 1000 psi. Extreme caution must be exercised when performing these tests to prevent personal injury.


The following procedure has been revised by a Technical
Service Bulletin.
1. Remove ECM cover/coolant reservoir and lay aside.
2. Open retaining clip from high pressure pipe.
3. Remove high pressure pipe from pump. Catch any fluid that may drain to avoid fluid seepage into engine and keep high pressure pipe away from belt.
4. Install power steering pressure gauge tool No. J-5176-D, or equivalent, as shown in Fig. 1.
5. Open valve on pressure gauge.
6. Start engine and allow system to reach operating temperature. Stop engine and check fluid level, add if necessary.
7. Start engine and check pressure.
8. Pressure reading should be under 181 psi. If pressure is above 181 psi, check hoses for restrictions.
9. With engine running, close valve fully three times for not more than five seconds each time. Each reading should show at least 1250 psi.
10. If pressures recorded are high enough and within 50 psi of each other, the pump is operating normally.
11. If pressures recorded are high enough but not within 50 psi of each other, the control valve in the pump is sticking. Remove but do not disassemble control valve and clean it with crocus cloth or a fine hone to remove any burrs.
12. If pressures recorded are less than 1250 psi, replace control valve and recheck. If pressures are still low, inspect pump rotor and vanes.
13. Shut off engine and remove pressure gauge.
14. Install high pressure pipe to pump and close retaining clip to pipe.
15. Install ECM cover/coolant reservoir.
16. Bleed system and check fluid level.