2.3L MCU Theory/Operation: Description

The MCU control system is named for and commanded by a Microprocessor Control Unit. This micro-computer is located in the engine compartment and is capable of controlling engine air/fuel ratios, air injection, and on some models, canister purge, spark retard and idle speed. The system consists of the MCU module, air/fuel control and air injection solenoids, engine sensors, feedback carburetor, and related circuitry.