Theory Of Operation

The Boost Pressure Actuator is an electronically operated DC motor designed to regulate the boost pressure output of the turbocharger. the boost pressure actuator is mounted on the side of the turbocharger assembly. The PCM will run a test to evaluate the response from the boost pressure actuator by commanding the actuator to move through its full position range for a calibrated time. During the test the PCM will evaluate the response based on a calculated characteristic value which is calculated from the exhaust pressure changes seen during the test. This test is only done once per drive cycle while the engine is idling and the engine coolant temperature is above 75°C (167°F).