Engine and Emission Control System Description — Fuel Pressure Regulator Control (Cont'd) / Acceleration Cut Control
EF & EC-20prose procedureFuel Pressure Regulator Control (Cont'd)
SYSTEM DESCRIPTION
The fuel "pressure-up" control system briefly increases fuel pressure for improved starting performance of a hot engine. Under normal operating conditions, manifold vacuum is applied to the fuel pressure regulator. When starting the engine, however, the E.C.U. allows current to flow through the ON/OFF solenoid valve in the control vacuum line, opening this line to the atmosphere. As a result, atmospheric pressure is applied, throttling the fuel passage to increase fuel pressure.
Fuel Pressure Regulator Control Timing Diagram
Rendering diagram…
Acceleration Cut Control
INPUT/OUTPUT SIGNAL LINE
Acceleration Cut Control Input/Output Signal Line
Throttle sensorE.C.C.S. control unit— Throttle valve opening angle
Crank angle sensorE.C.C.S. control unit— Engine speed
E.C.C.S. control unitAir conditioner relay
SYSTEM DESCRIPTION
When E.C.U. detects heavy load conditions, air conditioner is turned off for a few seconds. This system improves acceleration when air conditioner is used.