Computerized Engine Control Description

Electronic control system consists of airflow sensor position indicator (potentiometer), Electrohydraulic Actuator (EHA), Coolant Temperature Sensor (CTS), electronic CIS-E control unit, transistorized EZL ignition system, Throttle Valve Switch (TVS), engine systems control unit (MAS), heated oxygen sensor (Lambda control) and deceleration shut-off microswitch.

Fuel metering is achieved through CIS-E injection system. System is basic CIS injection with electronic controls added for mixture correction. Federal and California CIS-E control units are not interchangeable.

Spark timing is determined by CIS-E control unit and EZL electronic ignition system. Characteristics for various engine load conditions are stored in ignition control module.

On federal vehicles, CHECK ENGINE light only illuminates if oxygen sensor or lambda wiring system fails. On California vehicles, CHECK ENGINE light only illuminates if an emission control system malfunction occurs and is recorded in memory.

NOTE: Components are grouped into 2 categories. The first category covers INPUT DEVICES, which control or produce voltage signals monitored by the CIS-E control unit. The second category covers OUTPUT SIGNALS, which are components controlled by the CIS-E control unit.