Programmable fuel injection system (PGM-FI)
In the PGM-FI system, electrical pulses of precisely limited duration are used to control the injection of fuel through injectors directly into the intake port of each of the engine's combustion chambers. The moment and duration of the opening time of each of the injectors is controlled by the control module for the operation of the power unit (RSM). The PCM continuously monitors various operating parameters of the engine and, based on the incoming information, determines the required amount of fuel injected into each of the intake ports. The throttle body in this case serves only to control the air supply to the air supply system. Since each cylinder is equipped with its own injector, this scheme allows very precise control of the air-fuel mixture.
Fuel pump and fuel lines
The supply of fuel from the gas tank to the injection system and the return of its excess back to the gas tank is carried out through two metal lines laid under the bottom of the car. The submersible electric fuel pump is located inside the gas tank and is integrated into a single assembly with the fuel flow sensor unit. The fuel vapor return system carries out the removal of fuel vapors back to the gas tank through a separate return line. The fuel pump/fuel flow sensor assembly is accessed through the luggage compartment of the vehicle by removing the plastic cover.
Main relay PGM-FI (fuel pump relay) mounted on a bracket under the instrument panel on the driver's side of the car, to the left of the steering column. The operation of the relay is controlled by several different electrical circuits. One of these circuits receives battery voltage from the ignition switch. The second circuit is connected to the PCM, which produces a one-second relay closure. During engine cranking, the PCM closes the relay to ground until the piston position sensor (CYP) will not give the corresponding signal (see chapter Engine management). In the absence of reference pulses for two to three seconds, the pump is switched off. The third circuit de-energizes the relay when the clutch pedal is released (models with manual transmission), or when taken out of position "R" AT selector lever. This circuit is protected from overload by a 7.5 A fuse.
Exhaust system
The exhaust system of V6 models consists of a pair of exhaust manifolds, a Y-shaped exhaust pipe, a catalytic converter with an oxygen sensor located behind it (l-probe), muffler and exhaust pipe. On 4-cylinder models, the design of the exhaust system is even simpler, as the catalytic converter is connected by a downpipe to the engine's single exhaust manifold.
The catalytic converter is one of the main components of the emission control system. On the models under consideration, single-section converters with a 3-functional catalyst are used.