Section 5 (Fuel Injection System - BOSCH Cis): Description

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The Bosch Continuous Injection System (CIS) is a hydraulic-type fuel injection system which uses an air flow sensor, that is mechanically connected to a hydraulic valve, to control injection quantity.

The Lambda system is a feedback control capable of measuring air/fuel ratios and constantly correcting them. The combination of the two systems makes it possible to obtain both economy and performance, while minimizing exhaust emissions. See Fig 1 .

Fig 1: Bosch CIS Lambda Fuel Injection System Diagram (Typical)

The system consists of the mixture control unit (air-flow sensor and fuel distributor), control pressure regulator, auxiliary air valve, cold start valve, thermo-time switch, injector nozzles, fuel pump, filter, oxygen sensor, electronic control unit, frequency valve, and catalytic converter.

Some models use additional components, such as a thermo-vacuum valve, hot start pulse relay, or a constant idle speed control system.