Mirage L4-1597cc 1.6L DOHC Turbo (1989)
Fuel Pressure Control Solenoid: Description and Operation
Fuel Pressure Control Solenoid
The ECU uses the fuel pressure control solenoid to raise the fuel pressure from 26 PSI to 36 PSI during hot restart conditions. It does this by controlling
the vacuum to the fuel pressure control valve. By this method the chance of fuel boiling in the fuel rail is reduced.
When the ignition is turned on, the control relay applies 12 Volts to the solenoid. During cranking if the coolant temperature sensor indicates 194~F or
higher and the air temperature sensor indicates 122~ or higher, the ECU will ground the solenoid. As a result this will bleed off the vacuum and raise the
fuel pressure to 36 PSI. The ECU will keep the solenoid grounded for 2 minutes and increase the injector pulse width to help purge any fuel vapors in the
injectors.