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Boost Pressure Regulator: Non-APC

  1. Connect an air pressure gauge (83 92 813) between nipple on intake manifold and line to pressure switch. Run hose into passenger compartment and place gauge on left hand corner of instrument panel.
  2. Warm up engine. On manual transmission, drive vehicle in 3rd gear at an engine speed lower than 1500 RPM. On automatic transmission, place gear selector in position "1" at engine speed lower than 1500 RPM.
  3. On all models, accelerate at full throttle by pressing pedal to the floor. As engine speed approaches 3000 RPM, apply brakes while still keeping accelerator pedal pressed down.
  4. Note maximum pressure indicated with vehicle under full load at 3000 RPM. Charge pressure should be 6.7-7.8 psi (.46-.54 kg/cm2 ). Adjust boost pressure if necessary.
    NOTE: The boost pressure regulator valve and diaphragm unit assembly is factory set and should only be adjusted in conjunction with repairs, component replacement or during trouble shooting
    CAUTION: Hold diaphragm unit push rod to prevent from rotating when adjusting end piece. When holding, pliers should be positioned as close to thread as possible to avoid burring.