Sequential electronic fuel injection system (SFI)
Toyota and Lexus vehicles use fuel injection systems such as EFI (Electronic Fuel Injection) Or SFI Sequential Electronic Fuel Injection (Sequential Electronic Fuel Injection). The system uses predetermined pulses to inject fuel directly into the intake port of each cylinder in the order in which they fire. The injectors are controlled by the powertrain control module. This module monitors various parameters of the engine and gives the command to supply the exact amount of fuel (sets the cyclic feed) into the inlet channels. The amount of air entering the engine is controlled by the throttle body.
Fuel pump and fuel lines
Fuel with the help of a fuel pump built into the tank is supplied to the fuel rail through fuel lines running along the bottom of the car. The various sections of the fuel lines are either rigid metal or nylon lines or flexible hoses. Hose sections are connected by quick couplings. Inside the fuel tank is an electric fuel pump in a block with a fuel gauge sensor. In addition, a fuel pressure regulator is located in the fuel tank, which is an integral part of the fuel pump and the fuel gauge sensor unit.
Opening relay (fuel pump relay) It has primary and secondary circuits. The primary circuit is controlled by the PCM and the secondary circuit is connected directly to the main EFI relay via the ignition switch. With the ignition on (engine not running) The PCM grounds the relay for two seconds. When cranking the engine, the PCM provides ground to the beer pump turnpike while the camshaft position sensor (SMR) sends an appropriate position signal. If there are no reference pulses, the fuel pump turns off after two seconds.
Exhaust system
The exhaust system includes an exhaust manifold (s), various exhaust pipes, catalytic converters, muffler and rear exhaust pipe. On models 2001-2003. with a four-cylinder engine, three catalytic converters are provided: two front ones, which are an integral part of the exhaust manifold, and one rear converter, located under the bottom of the car. 2004 and later four-cylinder models have two catalytic converters: one front, which is an integral part of the exhaust manifold, and a rear converter, located under the bottom of the vehicle. All V6 models are equipped with three catalytic converters: two in the front, located just below each exhaust manifold, and a rear converter, located under the bottom of the vehicle. On models 1999-2003. The front converters are separate items that can be separated from the exhaust manifolds. On 2004 and later V6 models, front catalytic converters are an integral part of the exhaust manifolds. For more information about catalytic converters, see chapter 6.