MX-3 L4-1597cc 1.6L (1992)
fuel system pressure is increased by the same amount as manifold absolute pressure, maintaining a constant differential under changing engine
loads.
The pressure regulator control (PRC) solenoid, is installed in the vacuum line to the fuel pressure regulator. During hot re-start, the ECU energizes
the PRC solenoid valve, which blocks manifold vacuum to the pressure regulator and vents the regulator diaphragm chamber to the atmosphere.
With atmospheric pressure at the diaphragm, fuel pressure is increased. Increasing fuel pressure helps reduce fuel percolation due to heat. The
PRC solenoid is energized for about 50 seconds after the engine is started. After this time, the PRC solenoid is turned "OFF" and normal vacuum
modulation of fuel pressure is resumed.
