Mercury 25 EFI Service Manual page 169

Table of Contents
Theory of Operation........................................................... 3A-2
Air Induction System...................................................3A-2
Fuel System................................................................3A-2
Fuel Pump.................................................................. 3A-2
Vapor Separator......................................................... 3A-2
Fuel Pressure Regulator.............................................3A-3
Fuel Cooler................................................................. 3A-3
Throttle Body.............................................................. 3A-3
Sensors..............................................................................3A-3
Function of Sensors....................................................3A-3
Crank Position Sensor (CPS)..................................... 3A-4
90-8M0105568 eng MARCH 2016
Fuel System
Section 3A - Fuel System Operation
Engine Coolant Temperature (ECT) Sensor ..............3A-4
Manifold Absolute Pressure (MAP) Sensor................ 3A-4
Manifold Air Temperature (MAT) Sensor....................3A-5
Throttle Position Sensor (TPS)................................... 3A-5
Oil Pressure Switch.................................................... 3A-5
Actuators............................................................................3A-5
Function of Actuators..................................................3A-5
Engine Control Module............................................... 3A-5
Idle Air Control (IAC)...................................................3A-6
Fuel Injector................................................................ 3A-7
© 2016 Mercury Marine
Fuel System Operation
3
A
Page 3A-1