Golf III L4-2.0L (ABA) (1995)
EGR Temperature Sensor: Description and Operation
Exhaust Gas Recirculation Component Layout
EGR VALVE
The EGR valve meters exhaust gas into the intake system. The EGR valve is normally closed. When the system is operating, ported vacuum is applied to
the diaphragm chamber of the EGR valve, opening the valve during acceleration and cruising conditions.
EGR FREQUENCY VALVE
A solenoid operated vacuum switching valve is used to regulate the vacuum signal to the EGR valve. The valve is computer operated and works on a
duty cycle signal ("ON" time vs. "OFF" time). The valve gets battery power when the ignition is turned "ON" and is energized when the Engine Control
Module (ECM) completes the circuit to ground. When the engine reaches normal operating temperature, the ECM begins cycling the solenoid, allowing
the EGR system to operate.
EGR Temperature Sensor
EGR TEMPERATURE SENSOR
The EGR temperature sensor is used to inform the Motronic control module that the EGR valve is functioning. The sensor monitors the temperature of