EGR System - Diesel: Operation
The EGR flow is determined by position of throttle and EGR valves. Engine load information is signaled to EGR control unit by potentiometer installed on injection pump lever. Engine speed is signaled to control unit by a magnetic sensor on the injection pump. A water temperature sensor is located at water inlet.
The control unit signals the solenoid valves to open or close, determining vacuum levels at EGR control valve and throttle diaphragm. To make sure of good driveability, EGR is deactivated when engine temperatures are low or extremely high.
EGR SYSTEM OPERATION
| Throttle Valve | EGR Valve | EGR Rate |
|---|---|---|
| Closed | Open | High |
| Open | Open | Low |
| Open | Closed | Zero |