Mercedes Coupes/Sedans/Wagons 1974-1984 Repair Guide



This system was used on 1976-84 vehicles.

This system replaces the electronic system of earlier years. In contrast to the intermittent type fuel injection, this system measures air volume through and air flow sensor and injects fuel continuously in front of the intake valves, regardless of firing position.

Minor running changes and improvements are made during production, but essential operation and service of the system remains alike on all vehicles equipped with the CIS injection.

The 190E utilizes an electronically controlled version of the K-Jetronic injection system called KE-Jetronic (CIS-E). This system is a further development of the mechanically controlled CIS system. The essential difference between the two is mixture correction by means of electronically controlled correction functions (CIS-E). An electronic control unit sends out impulses which effect the amount of fuel being injected. Since only the mixture corrections are controlled by this new system, the vehicle will continue to operate if there is an electronic malfunction.

Even a seemingly minor adjustment, such as idle speed, can necessitate adjustments to other portions of the fuel injection system. Be extremely careful when adjusting the idle. If any difficulty at all is experienced, it will only upset the balance of an already delicate system.