System Operation

When engine coolant temperature is less than 131°F (55°C), EGR operation is cancelled by PCM to improve driveability. When engine is warm, EGR operation is controlled by PCM and EGR Vacuum Regulator (EVR) solenoid. PCM utilizes inputs from Differential Pressure Feedback EGR (DPFE) sensor along with other sensor inputs to properly balance EGR flow. See Figure .