SFI Sequential Multiport Fuel Injection System

• An L-type SFI system directly detects the intake air mass with a hot wire type mass air flow meter.

• An independent injection system (in which fuel is injected once into each cylinder for each two revolution of the crankshaft) is used.

• There are two (synchronous and non-synchronous) injections:

a) The synchronous injection in which corrections based on the signals from the sensors are added to the basic injection time so that injection occurs always at the same position.

b) The non-synchronous injection in which injection is effected by detecting the requests from the signals of the sensors regardless of the crankshaft angle.

Furthermore, to protect the engine and achieve lower fuel consumption, the system uses a fuel cutoff in which the injection of fuel is stopped temporarily in accordance with the driving conditions.

• This system performs group injection when the engine coolant temperature is extremely low and the engine is operating at a low speed.

Synchronous Injection

Non-synchronous Injection







0° 120° 240° 360° 480° 600° 720° Crankshaft Angle Independent Injection 238EG70

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  • erik
    How to sfi sistam in Toyota car?
    1 year ago
  • eglantine
    What is toyota SFI (Sequential Multiport Fuel Injection) system?
    3 months ago

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