Throttle Body Fuel Injection (TBI) — An Integrated Engine Control System

Presented is a technical description of the significant features of the General Motors developed Throttle Body Fuel Injection System in production on the 1980 Cadillac Eldorado and Seville passenger cars. TBI fuel system discussion is divided into the 69 kPa (10 psi) fuel system, injector performance, fuel pump, sensors, electronic control module and system fuel control philosophy based upon speed density.

Since achievement of low operating pressure for the fuel injection system is a significant technical accomplishment, the TBI fuel system design to accommodate hot fuel conditions will be reviewed.