Turbocharger control is based off an air system model that produces a desired intake pressure to meet the power
requirements requested by the operator.. The PCM commands the VGT control valve by a feedback loop on the intake
pressure to achieve the desired intake pressure to meet the driver’s needs (pedal position, engine load). The air system
model considers engine temperature, air temperature, EGR operation, RPM, and engine load.
The turbocharger on pickup box models have a wastegate. The PCM controls the wastegate solenoid to supply vacuum
to the actuator. When intake pressure is greater than desired and the VGT has commanded the vanes to the full open
position the wastegate opens allowing exhaust gases to bypass the turbine fins, reducing exhaust pressure thus reducing intake pressure.
