Lucas mechanical fuel injection system

In the Lucas system, fuel from the tank is pumped at high pressure to a fuel accumulator. From there it passes into the fuel distributor, which sends a burst of fuel to each injector, from where it is fired into the inlet port.

The airflow is controlled by a flap valve which opens in response to the accelerator pedal. As the airflow increases, the fuel distributor automatically increases the flow of fuel to the injectors to keep the fuel/air mixture correctly balanced.

For cold starting, a choke on the dash or, on later models, a microprocessor control unit brings a special cold-start injector into operation, which injects extra fuel to create a richer mixture. Once the engine has warmed up to a certain temperature, a thermoswitch automatically cuts off the cold-start injector.

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How a fuel injection system works

For the engine to run smoothly and efficiently it needs to be provided with the right quantity of...