System Description

Fig. 1 CEC system. 1984 - 87 6-258:

Fig. 2 CEC system wiring diagram. 1984 - 87 6-258:

This system, Figs. 1 and 2, controls the air fuel ratio through the use of various engine sensors that monitor engine operating conditions, a micro computer unit (MCU) that processes the signal from the sensors and a [1][2]stepper motor (6-258) or mixture control solenoid (4-150) located inside the carburetor that controls the air/fuel ratio according to the signals received. During operation, this system maintains the engine in either the closed loop or open loop mode of operation.
This system also reduces undesirable exhaust emissions in conjunction with either a three-way or a dual bed converter, while maintaining good fuel economy and engine performance.
During operation, the primary feedback data is provided by an oxygen sensor located in the exhaust system. This sensor provides a voltage that is proportional to the amount of oxygen present in the exhaust gases. This data is used to regulate and optimize the air/fuel mixture.