Electronic control common rail type fuel injection system drives an integrated fuel pump at an ultrahigh pressure to distribute fuel to each injector per cylinder through a common rail. This enables optimum combustion to generate big horsepower, and reduce PM* (diesel plume) and fuel consumption. Bosch will supply the complete common-rail injection system for the high-performance 12-cylinder engine introduced by Peugeot Sport for its latest racing car. The system comprises high-pressure pumps, a fuel rail shared by all cylinders (i.e. a common rail), piezo in-line injectors, and the central control unit which compiles and processes all relevant sensor data.
To understand the basics of the automotive fuel systems used today is pretty simple. Understanding these fuel systems will definitely increase your confidence in sales and more importantly the confidence of your customers. Most vehicles in use today are powered by gasoline or diesel fuel, although alternative fuel vehicles powered by E8 5, natural gas, propane, and combinations of fuels are common. Bi-fuel vehicles have two separate fuel systems, where either one can power the vehicle. One fuel system is designed to run on gasoline and the other is designed for CNG (Compressed Natural Gas) or LPG (propane). There are dedicated CNG and LPG powered vehicles, with LPG being the most common. Hybrid vehicles use a combination of conventional fuel and electric power. They can operate on either conventional fuel with a small four-stroke piston engine or with an onboard electric motor and battery system. In most cases the gasoline engine is the primary power source and the electric motor is used as an assist, particularly at take off and higher speeds. This allows a smaller, more fuel efficient engine to be used. When the vehicle comes to a stop the engine may shut down completely, and when the throttle pedal is depressed the electric motor will provide the initial power with the gas engine starting as the vehicle begins to move. Battery charging is provided by the gas engine and through regenerative braking. Vehicles built today use some form of fuel injection system. The most common major components of a gasoline or diesel fuel system are the intake manifold, throttle body (except diesel), air filter, fuel injectors, PCM/ECM, wiring harnesses, airflow meter, fuel filter, fuel pump, fuel tank, fuel lines and pressure regulator.
The rules for plastic fuel tanks have changed. The US Environmental Protection Agency (EPA) has published evaporative emission requirements for fuel systems on recreational boats. When purchasing plastic tanks be sure to ask your supplier if they meet the EPA standards.
The key to an efficient electronic fuel injection system is a computer. All modern injection systems (as well as some carburetor systems) utilize some type of computer. The automotive industry has many names for these computers. Depending on the manufacturer, the computer may be called:
Fuel filters are an important part of every fuel system. They will vary in size and shape; some are mounted under the hood with the engine, while others are placed somewhere between the gas tank and the engine, or in the fuel tank. The common arrangement for a fuel injected vehicle is an in-tank fllter or screen that is not serviced as normal maintenance and an inline filter that is serviced as part of the maintenance schedule. Fuel must be moved from the fuel tank to the engine. This is done by means of a fuel pump, usually mounted inside the fuel tank. Some in-tank units are combination fuel pumps and fuel sending units for the vehicle’s fuel gauge. Many vehicles have an inertia switch that shuts off the fuel pump if the vehicle is involved in a collision. OBD II vehicles use pressure sensors and vapor control systems called Evaporative systems to capture fuel vapors during normal operation of the vehicle and draw them into the engine to be burned. The PCM/ECM monitors fuel tank pressure to determine the presence of system leaks. If a fuel cap is left off it can cause the MIL (Malfunction Indicator Light) to illuminate until the cap is replaced and, in some cases, the related DTC (Diagnostic Trouble Code) is cleared. Fuel lines carry fuel from the fuel tank to the fuel injection system. They are usually made from metal tubing or flexible hose. The hoses and tubes have to be specially designed to be used with fuel.