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Electronic Fuel Injection System

NOTE: Only those components directly used in the Constant Idle Speed system will be covered in this section. For information on fuel injection system, refer to appropriate FUEL INJECTION SYSTEM - BOSCH LH JETRONIC II article.

The LH-Jetronic fuel injection system consists of 3 functional sections: ECU, fuel system and sensors. ECU receives and evaluates readings from various sensors around engine. Microprocessor evaluates variations in engine running conditions, calculates correct amount of fuel to be injected, and produces corresponding signals to injectors. It also operates air control valve for constant idle speed by regulating airflow opening. See Fig 1 .

Fig 1: Electronic Fuel Injection System With Integral Constant Idle Speed Control System
G42210Courtesy of VOLVO CARS OF NORTH AMERICA.