Eighty-Eight Royale FWD V6-3.8L VIN K (1996)
Boost Solenoid: Description and Operation
Boost Control System
The boost control system regulates induction boost pressure during rapid deceleration, under very high engine load situations, and anytime reverse
gear is selected.
Under most conditions, the PCM commands the boost control solenoid to operate at a 100% duty cycle (ON), keeping the solenoid valve closed
and allowing only inlet vacuum to control the position of the bypass valve. At idle, full inlet vacuum applied to one side of the bypass valve
actuator diaphragm counteracts spring tension to hold bypass valve open. As engine load increases, reduced vacuum acts upon the spring tension
in the bypass valve actuator, causing the bypass valve to close and increasing boost pressure.
When reduced boost pressure is desired, the PCM commands the boost control solenoid to operate at a 0% duty cycle (OFF). This opens the
solenoid valve and allows boost pressure from the intake manifold to counteract the spring tension in the bypass valve actuator, opening the bypass
valve and recirculating excess boost pressure back into the supercharger inlet. With reverse gear selected, the PCM commands the boost control
solenoid to operate at a 0% duty cycle (OFF) at all times.
LEGEND
(1) Vacuum Signal to Supercharger Bypass Actuator
(2) Boost Signal to Fuel Pressure Regulator
(3) Supercharger Bypass Actuator
(4) Boost Signal to Supercharger Bypass Actuator
(5) Supercharger Bypass Solenoid
(6) Boost Source to Supercharger Bypass Solenoid
