fuel injection

(redirected from Electronic fuel injection)
Also found in: Dictionary, Thesaurus, Acronyms.

fuel injection,

system in an internal-combustion engineinternal-combustion engine,
one in which combustion of the fuel takes place in a confined space, producing expanding gases that are used directly to provide mechanical power.
..... Click the link for more information.
 that delivers fuel or a fuel-air mixture to the cylinders by means of pressure from a pump. It was originally used in diesel enginesdiesel engine,
type of internal-combustion engine invented by the German engineer Rudolf Diesel and patented by him in 1892. Although his engine was designed to use coal dust as fuel, the diesel engine now burns fuel oil.
..... Click the link for more information.
 because of diesel fuel's greater viscosity and the need to overcome the high pressure of the compressed air in the cylinders. A diesel fuel injector sprays an intermittent, timed, metered quantity of fuel into a cylinder, distributing the fuel throughout the air within. Fuel injection is also now used in gasoline engines in place of a carburetorcarburetor
, part of a gasoline engine in which liquid fuel is converted into a vapor and mixed with a regulated amount of air for combustion in the cylinders. Land vehicles, boats, and light aircraft have a float carburetor, in which a float regulates the fuel level in a
..... Click the link for more information.
. In gasoline engines the fuel usually is injected into the intake manifold and mixed with air, and the resulting mixture is delivered to the cylinder. Modern fuel injection systems use computers to regulate the process. Fuel injection results in more efficient fuel combustion, improving fuel economy and engine performance and reducing polluting exhaust emissions.

fuel injection

[′fyül in‚jek·shən]
(mechanical engineering)
The delivery of fuel to an internal combustion engine cylinder by pressure from a mechanical pump.

Fuel injection

The pressurized delivery of a metered amount of fuel into the intake airflow or combustion chambers of an internal combustion engine. Metering of the fuel charge may be performed mechanically or electronically. In a diesel engine, the fuel is injected directly into the combustion chamber (direct injection) or into a smaller connected auxiliary chamber (indirect injection). In the spark-ignition engine, the fuel is injected into the air before it enters the combustion chamber by spraying the fuel into the airstream passing through the throttle body (throttle-body injection) or into the air flowing through the port to the intake valve (port injection). See Combustion chamber

The diesel engine must be supplied with fuel from the injection nozzle at a pressure of 1500–5000 lb/in.2 (10–35 megapascals) for indirect-injection engines, and up to 15,000 lb/in.2 (100 MPa) or higher for direct-injection engines. The high pressure is necessary to deliver fuel against the highly compressed air in the engine cylinders at the end of the compression stroke, and to break up the fuel oil which has low volatility and is often viscous. Extremely accurate fuel metering is necessary, with the start of injection occurring within a precision of up to 1° of engine crankshaft angle. A timing device in the injection pump automatically advances the start of fuel delivery as engine speed increases to optimize the start of combustion.

The intake air is not throttled in a diesel engine, with load and speed control accomplished solely by controlling the quantity of fuel injected. The mean effective pressure developed by combustion is controlled by the volumetric capacity of the injection pump. To prevent an unloaded diesel engine from increasing in speed until it destroys itself, a governor is required to limit maximum engine speed. See Diesel engine, Internal combustion engine, Mean effective pressure

On automotive spark-ignition engines, the carburetor has largely been replaced by a gasoline fuel-injection system with either mechanical or electronic control of fuel metering. Many of the systems are of the speed-density type, in which the mass airflow rate is calculated based on cylinder displacement and the measured intake-manifold absolute pressure (engine load), engine speed, intake-manifold air temperature, and theoretical volumetric efficiency. When the feedback signal from an exhaust-gas oxygen sensor is included, these systems allow the engine air-fuel ratio to be maintained near the stoichiometric ratio (14.7:1) during normal operating conditions. This minimizes exhaust emissions. See Carburetor

In the typical gasoline fuel-injection system, an electric fuel pump provides a specified fuel flow at the required system pressure to one or more fuel-injection valves, or fuel injectors. The gasoline fuel injector is an electromagnetic (solenoid-operated) or mechanical device used to direct delivery of or to meter pressurized fuel, or both. A fuel-pressure regulator maintains a controlled fuel pressure at each injector, or a controlled differential pressure across the injector. See Fuel pump, Fuel system

fuel injection

fuel injectionclick for a larger image
A form of a fuel-metering system for a reciprocating engine that injects fuel directly into the cylinder rather than mixing it with air before it is taken in through the intake valve. The two types of fuel injection systems are the direct injection system (for diesel engines) and the continuous-flow fuel injection system (for horizontally opposed engines).
References in periodicals archive ?
POLARIS Polaris Sportsman 850 XP EFI boasts a powerful 70 hp, 850cc twin-cylinder, tourstroke engine with electronic fuel injection.
In recent years the volume of production of carburetors has declined sharply, as more new cars are equipped with electronic fuel injection systems.
The PGM-FI electronic fuel injection system and lean-burn(4) control during cruising(5) allow the BF60 to offer best-in-class(6) fuel economy.
Holley carburetors have powered every NASCAR Cup Series team since the 1960's and Holley now supplies NASCAR with high performance electronic fuel injection throttle bodies as the teams transition to electronic fuel injection for the 2012 race season.
Although capacity changed from 757cc, to 850cc then 1,000cc before settling for the 1,100ccs that it boasts today, the California has always used Moto Guzzi's traditional 90A V-twin configuration, with electronic fuel injection modernising later models ( more technical trickery for the day, Moto Guzzis were full of them.
In Thailand, in 2003, Honda introduced the first model equipped with an electronic fuel injection system, PGM-FI (Honda Programmed Fuel Injection), which achieves improved fuel economy and cleaner emissions as well as excellent start-up capabilities.
7 Engine features electronic fuel injection and electronic engine controls for easy starting and fuel efficiency.
5-litre four-cylinder powerplant offers multi-port electronic fuel injection, double overhead camshafts and tuned intake and exhaust manifolds.
Low cost electronic fuel injection for 2 and 3 wheeled motorcycles
This report covers the global two wheeler fuel injection systems market, which is broadly segmented by technology Carbeureted Fuel Injection System (CFI), and Electronic fuel injection (EFI) system which is further segmented into Multi-Pont Fuel Injection System (MPFI).
They are also planning to produce a new electronic fuel injection system that will help improve fuel efficiency for bikes.
26 at the venerable Daytona 500 race when, for the first time in its 64-year history, the cars in the NASCAR Sprint Cup Series will race across the starting line using electronic fuel injection (EFI) made possible by Freescale Semiconductor (NYSE: FSL) and McLaren Electronic Systems.

Full browser ?