Fuel Charging and Controls
The fuel charging and controls system consists of the:^ throttle body
^ fuel injector
^ fuel charging wiring
^ fuel injection supply manifold with the fuel injector pressure sensor
^ fuel pressure relief valve
The fuel charging and controls system is:
^ a Sequential Multiport Fuel Injection (SFI) system
^ pulse-width modulated
^ mass air flow controlled
The Powertrain Control Module (PCM) controls the fuel injection system. Injector pulse-width is varied to control the amount of fuel flow through the injectors and into the engine. Varying fuel pump output controls fuel pressure. The PCM commands the fuel pump driver module, which directly controls the fuel pump.
The fuel injection supply manifold:
^ delivers fuel to the individual fuel injectors
^ receives fuel from the fuel supply line
The throttle body:
^ controls air supply to the upper intake manifold by positioning the throttle plate
^ connects the accelerator cable and, if equipped, speed control actuator cable to the throttle plate
^ is not adjustable
^ cannot be cleaned
The fuel injectors:
^ are electrically operated by the powertrain control module
^ have an internal solenoid which opens a needle valve to inject fuel into the lower intake manifold
^ atomize the fuel as it is delivered
^ are deposit-resistant