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Fuel Injectors

Fuel injectors in CIS system open at a pre-set pressure. Fuel is always present in lines between fuel distributor and injectors to ensure good starting. As pressure from fuel distributor increases (when engine is started), valves open and spray constantly. Amount of fuel injected will be determined by position of control plunger in fuel distributor. See Fig 1 .

Fig 1: Bosch CIS (Lambda) Fuel Injector Pin in injector vibrates to atomize fuel.
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