STANDARDS FORCE MOVE TO ELECTRONIC ENGINE CONTROLS.

The Ford and Cadillac electronic fuel injection (EFI) systems and the Chrysler electronic feedback carburetors, all using on-board microprocessors, are described. The Ford and Cadillac EFI systems are both of the throttle-body type. Ford and Cadillac have both changed from analog to digital devices. In Chrysler's system sensors in the exhaust manifold monitor oxygen content on the exhaust and relay that information to the computer. The computer adjusts the air fuel mixture to maintain stoichiometry, which is the most efficient combustion process. At stoichiometry the engine is able to produce a minimum of emissions yet maintain good driveability. The feedback carburetor is also used with an air pump and three-way catalyst to control emissions.