Fuel Injection System - BOSCH Cis: Description

Bosch Continuous Injection System (CIS) is a mechanical fuel injection system which uses airflow sensor assembly connected to fuel distributor to control injection quantity.

Lambda is a feedback control system capable of continuously measuring and correcting air/fuel ratios. Combination of 2 systems allows for both economy and performance with minimal exhaust emissions. See Fig 1 .

Fig 1: Bosch CIS Lambda Fuel Injection System Diagram This illustration is typical of all models. Specific details among models may vary.

System consists of mixture control unit (airflow sensor and fuel distributor), control pressure (warm-up) regulator, auxiliary air regulator, cold start valve, thermo time switch, fuel injectors, fuel pump, filter, oxygen (O2) sensor, electronic control unit (ECU), frequency valve and catalytic converter.

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