Dateline: Detroit, Michigan, 1981—in an effort to meet more stringent exhaust emissions and fuel economy standards, automakers have developed on-board computerized engine controls. With ignition ...

Here's what drives cars of the '80sâ the Electronic Computer Module(ECM).Typical GM unit has an analog board to run sensors, digital board for"thinking" and memory. Removable PROM(at left)calibrates ...