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Proportioning Valve

WARNING: This page is about a different car, the 1993 Plymouth Laser, 1993 Eagle Talon, 1992 Plymouth Laser, and 1992 Eagle Talon. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: Under normal conditions, input and output pressures increase gradually (but not equally) as brake pedal is pressed. At certain point, output pressure begins to drop while input pressure continues to increase. This point is referred to as "split point".
  1. Connect 2 pressure gauges, one to input side and one to output side of proportioning valve. Bleed air from brake line and pressure gauges.
  2. Gradually press brake pedal and observe pressure gauges. If split point occurs at 491-561 psi (AWD vehicles), or 561-633 psi (FWD vehicles), go to next step. If split point does not occur at specified pressure, replace proportioning valve.
  3. Gradually press brake pedal until input pressure is as specified in INPUT-TO-OUTPUT PRESSURE COMPARISON  table. If output pressure is as specified, proportioning valve is okay. If output pressure is not as specified, replace proportioning valve.
INPUT-TO-OUTPUT PRESSURE COMPARISON (1)

Application Input Pressure Output Pressure
All-Wheel Drive (AWD) 1095 psi 661-732 psi
Front-Wheel Drive (FWD) 1163 psi 732-804 psi
(1) Press brake pedal until input pressure is as specified, then read output pressure.