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Pressure Test

  1. On vehicles without Two Flow Electronic (TFE) steering, go to step 3). On TFE-equipped vehicles, check normal system operation. Start engine and turn wheels from side to side. Wheels should turn with minimal effort. Wait 3 minutes and repeat previous step. Increased effort should be required to turn wheels.
  2. If system operation is not as specified, troubleshoot and repair as necessary. If system operation is as specified, connect fused jumper between terminal B8 of multi-function chime module and terminal 4 of DLC, to enable full fluid flow. Go to next step.
  3. Disconnect high pressure line from power steering pump. Connect Power Steering Pressure Tester Kit (J-5176-D), or Power Steering Analyzer (J-25323) with Adapter (J-28579), between high pressure line and power steering pump using spare high pressure hose. Completely open tester valve.
  4. Run engine until fluid reaches operating temperature. Stop engine. Check fluid level. Add fluid if necessary. Start engine. With valve open and engine idling, pressure should be less than 150 psi (10.5 kg/cm2 ). If pressure exceeds specification, stop engine and check for restrictions in hoses.
    CAUTION: To prevent pump damage, DO NOT  hold gauge valve closed for more than 5 seconds.
  5. Fully close valve for less than 5 seconds and then open it. Repeat process 2 more times, and record highest pressure displayed each time valve is closed. If readings are as specified and within 50 psi (3.5 kg/cm2 ) of each other, go to step 8). Refer to the PRESSURE SPECIFICATIONS  table below. If readings are as specified but not within 50 psi (3.5 kg/cm2 ) of each other, go to next step. If readings are not as specified but within 50 psi (3.5 kg/cm2 ) of each other, go to step 7).
    PRESSURE SPECIFICATIONS

    Application psi (kg/cm2 )
    "A" Bodies More Than 1000 (70)
  6. Flow control valve is sticking. Remove valve but DO NOT  disassemble. Clean valve using crocus cloth or fine hone. Flush system if dirty. Install valve. Recheck pressure. If readings are now as specified, go to step 8).
  7. Replace flow control valve and retest system. If pressure readings are still low, check pump rotor and vanes for wear. Replace complete pump assembly if worn.
  8. With valve open, turn steering wheel from stop to stop. Record highest pressure with wheels at both stops. If highest pressure is not equal to highest pressure recorded in step 5), rack and pinion assembly is leaking internally. Repair or replace assembly. If pressures are equal, no problem exists. Go to next step.
  9. Turn engine off. Remove tester. Reconnect high pressure hose to pump. Check fluid level. Bleed hydraulic system. Refer to HYDRAULIC SYSTEM BLEEDING  under LUBRICATION.