Spark Control Computer: Notes

The Spark Control Computer (SCC) is mounted on the left inner fender panel (Pickup models) and center of the firewall (Van models). The SCC consists of a printed circuit board which simultaneously receives signals from all data sensors and analyzes these signals to determine spark advance and, on models with feedback carburetor, the air/fuel mixture. Incorporated within the computer are the electronics for throttle control, EGR and air switching systems. After determining spark advance, the computer operates the engine feedback system (on models so equipped) in one of the following modes: