Fuel Injection System - TBI: Description
The Chrysler Throttle Body Injection (TBI) system is computer controlled and utilizes a throttle-body assembly with a single fuel injector.
Fuel is supplied to the engine through an electronically controlled injector located in the throttle body assembly on top of the intake manifold. A Single Module Engine Controller (SMEC) supplies power to the injector and determines the length of time the injector is left open.
The SMEC is a pre-programmed computer which controls ignition timing, emission control devices and idle speed in addition to air/fuel ratio. The amount of fuel to be metered through the injector is based on engine operating condition information as supplied by various engine sensors and switches. These include the Manifold Absolute Pressure (MAP) sensor, Throttle Position Sensor (TPS), oxygen sensor, coolant temperature sensor, vehicle distance/speed sensor and throttle body temperature sensor.