Fuel injection is now the preferred way of getting the fuel mix to the combustion chamber in both petrol and diesel engines. The fuel injection system measures the fuel mix much more precisely than a carburettor does.

Fuel injection systems found in petrol driven vehicles can be classified by the way in which they inject the fuel mix into the combustion chamber. A continuous injection system sprays fuel continuously from the injectors, and the amount of fuel sprayed out is controlled by changing the pressure at which the fuel is forced through the injectors. The greater the pressure, the more fuel is injected into the chambers. An intermittent injection system pulses on and off to control the amount of fuel entering the combustion chamber. When more fuel mix is required, the time the injector is pulsed on is increased. The sequential injection system has generally one injector per cylinder. Each injector fires independently and in relation to the position of the intake valves.

In a diesel fuel-injection system, there are two different methods of diesel fuel injection. In the air injection system, a blast of air from an external source forces a measured amount of fuel into the cylinder. In the mechanical injection system, fuel is forced into the cylinder by hydraulic pressure on the fuel. In diesel engines, the mechanical injection system is the most common type.

Because the fuel injection system measures the fuel mix with precision, fuel economy and power delivery is enhanced tremendously over the carburettor system, which allows the fuel mix to be drawn in to the combustion chamber.We hope that helps answer the question ‘What is What is Fuel-Injection?’!

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