The Boost Pressure Sensor (BPS) is located in the intake air tube between the turbocharger inter cooler and the throttle body. The BPS measures the throttle inlet pressure. The ECM uses the information from the BPS to refine the estimate of the airflow rate through the throttle and to determine the desired boost pressure. The BPS for a speed density system is integrated with the turbocharger inter cooler temperature sensor.

The turbocharger wastegate regulating valve solenoid allows the PCM to control the turbocharger wastegate position. The turbocharger wastegate regulating valve solenoid controls the pressure or vacuum supplied to the pneumatically actuated wastegate diaphragm in order to control the boost pressure limit. When the compressor outlet pressure increases, a pneumatically powered actuator opens the turbocharger wastegate and limits the compressor outlet pressure. The turbocharger wastegate regulating valve solenoid supplies pressure or vacuum to the pneumatically actuated wastegate canister diaphragm, which regulates the boost pressure to the desired value.