EGR Valve Position Sensor: Description and Operation

PURPOSE
Senses position of the Exhaust Gas Recirculation (EGR) valve and sends this information to the engine control electronics.

OPERATION
The sensor uses a plunger operated potentiometer supplying a signal to the Engine Control Module (ECM). The ECM contains memories for optimum EGR lift during various conditions. The lift sensor sends information on actual EGR valve lift to the ECM. If the EGR valve's actual position differs from the preferred position, the ECM cuts power to the control solenoid to reduce vacuum applied to the EGR valve.

CONSTRUCTION
The sensor uses a plunger operated potentiometer attached directly to the top of the EGR valve, and is not available separately.