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Pressure Test

WARNING: This page does not describe the selected car, but rather 32 other vehicles, including the 1990 Pontiac Trans Sport, 1990 Oldsmobile Silhouette, 1990 GMC Vandura Special, 1990 GMC Vandura, and 1990 GMC Value Van. However, it is still accessible from the selected car via links, so may be relevant.
  1. Note pressure reading with valve open and engine idling. Pressure should be 80-125 psi (6-9 kg/cm2 ). If pressure is above 200 psi (14 kg/cm2 ), check hoses for restrictions and poppet valve for proper assembly.
  2. Close gate valve completely and reopen 3 times. Record highest reading each time. DO NOT  close valve for more than 5 seconds. Reading should be within specification. On "G", "P", and "R" & "V" series, see appropriate PUMP SPECIFICATIONS  below. On all other models, see PRESSURE TEST SPECIFICATIONS  table.
  3. If readings are within specification and within 50 psi (4 kg/cm2 ) of each other, pump is operating properly. On "G", "P", and "R" & "V" series, see appropriate PUMP SPECIFICATIONS  below. On all other models, see PRESSURE TEST SPECIFICATIONS  table.
  4. If pressures are high, but do not repeat within 50 psi (4 kg/cm2 ), flow control valve in pump is sticking. Remove flow control valve. Clean or replace flow control valve.
  5. If pressure is constant, but more than 100 psi (7 kg/cm2 ) less than specification, clean or replace flow control valve in pump. If pressures are still low, replace pump.
  6. If pump is within specification, open valve and turn steering wheel from right to left stops. Record pressure. DO NOT  hold wheel against stops more than 5 seconds.
  7. Pressure should be within specification. On "G", "P", and "R" & "V" series, appropriate PUMP SPECIFICATIONS  below. On all other models, see PRESSURE TEST SPECIFICATIONS  table. If pressure is low, steering gear is leaking internally and must be repaired.
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