Modern and conventional gasoline engines have been designed to use an electronic fuel injection system that replaces the traditional mechanical carburettor system. Multi-point injection (MPI), where the fuel is injected through each intake port, is currently one of the most extensively used systems. Although MPI provides a drastic step up in response and combustion quality, it is still limited because of the fuel and air mixing prior to entering the combustion chamber in the cylinder.

To increase an engine’s response time and combustion efficiency further – while lowering fuel consumption and increasing output – fuel injection systems may use the direct injection procedure. Petrol direct-injection engines are engineered to inject the gasoline directly into the cylinder in a manner similar to diesel direct injection engines.

Direct injection engines have been designed to allow greater control and precision, resulting in better fuel economy. This is accomplished by enabling the combustion of an ultra-lean mixture of fuel and air under many engine operating conditions. Direct injection gives the option of using higher compression ratios; it also delivers higher performance and better fuel economy.

We hope that helps answer the question ‘What is What is Direct Injection?’!

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