EGR Position Sensor

The PCM calculates ideal EGR valve lifts for varying operating conditions. The EGR position sensor detects amount of EGR valve lift and sends the information to the PCM. PCM compares this information (actual EGR valve lift) with ideal EGR valve lift. If the 2 signals differ, the PCM closes the EGR control solenoid valve to reduce vacuum applied to the EGR valve.