Computers and Control Systems: Description and Operation

Fig. 2 Closed Loop Emission Control system schematic.:

The Closed Loop Emission Control System, Fig. 2 is used on all California Pick-up models. The system is used to provide precise control of the air/fuel mixtures, allowing use of a dual bed 3-way catalytic converter and to control air flow in the AIR system. System components include an electronic Control Module (ECM), oxygen sensor, vacuum fuel control valve and duty solenoid, electronically controlled carburetor and other sensors and actuators. The three-way catalytic converter is also considered part of this system.