EGR Control Solenoid: Testing and Inspection
PRE-TEST REQUIREMENTSEngine coolant temperature at least 176°F (80°C)
All electrical consumers (including A/C) switched OFF.
Radiator fan must not run while performing tests
Vacuum connections tight and without leaks
Vacuum hoses not pinched or plugged
TOOL REQUIREMENTS
Digital Volt/Ohm Meter (DVOM)
Test Connector kit VW 1594 or Equivalent
Refer to Tools and Equipment for test equipment specifications.
TEST PROCEDURE
- Ignition switch OFF.
EGR System:
- Disconnect EGR frequency valve harness connector.Mounted on the back of the intake manifold.
- Using DVOM check resistance between frequency valve terminals.
- Must be 25 - 35 ohms
- IF NOT replace EGR frequency valve
Fig. 10 Checking Frequency Valve Duty Cycle:
- Using a test harness that allows the frequency valve to remain connected while testing (VAG 1594 or equivalent) connect VAG 1367 tester (or a suitable duty cycle meter) to the connectors as shown.
- START engine and raise RPM to about 2000.
- Duty cycle should be 32° ± 10% at 2000 RPM.
NOTE: The duty cycle is first triggered at 1000 RPM. Therefore, duty cycle will not register below 1000 RPM.
- If the frequency valve duty cycle is not within specifications:
- Check pre-test requirements
- Check the wiring, refer to VAG 1598 Pin Out Box/ Electrical Checks, repair as necessary.
- Turn ignition switch OFF, disconnect tester and test harness.
- Re-connect frequency valve harness connector.