Exhaust Gas Recirculation: Testing and Inspection

1. Using a three-way connector, connect a suitable vacuum gauge between the EGR and EGR vacuum modulator.
2. Start engine and ensure engine idles normally.
3. Check EVSV with coolant temperature below 102.2°F. Ensure vacuum gauge reads zero.
4. Warm engine. Ensure vacuum gauge registers a high vacuum reading with engine speed at 3000 RPM.
5. Apply vacuum to EGR valve. Ensure engine runs rough or stalls.
6. If no problems are found, the system is operation correctly.
7. If any condition fails, check and repair and/or replace part found defective.