Exhaust Gas Recirculation: Testing and Inspection

EGR SYSTEM INSPECTION





1. INSPECT AND CLEAN FILTER IN EGR VACUUM MODULATOR
- Remove the cap and filter.
- Check the filter for contamination or damage.
- Using compressed air, clean the filter.





- Reinstall the filter and cap.

HINT: Install the filter with the coarser surface facing the atmospheric side (outward).

2. INSTALL VACUUM GAUGE
- Using a 3-way connector, connect a vacuum gauge to the hose between EGR valve and VSV.
3. INSPECT SEATING OF EGR VALVE
- Start the engine and check that the engine starts and runs at idle.





4. CONNECT TERMINALS TE1 AND E1 OF DATA LINK CONNECTOR I
- Using SST, connect terminals TE1 and E1 of the data link connector 1. SST 09843-18020
5. INSPECT VSV OPERATION WITH COLD ENGINE
- The engine coolant temperature should be below 47°C (117°F).
- Check that the vacuum gauge indicates zero at 2,500 rpm.





6. INSPECT OPERATION OF VSV AND EGR VACUUM MODULATOR WITH HOT ENGINE
- Warm up the engine to above 53°C (127°F).
- Check that the vacuum gauge indicates low vacuum at 2,500 rpm.
- Disconnect the vacuum hose from port R of the EGR vacuum modulator and connect port R directly to the intake manifold with another hose.
- Check that the vacuum gauge indicates high vacuum at 2,500 rpm.

HINT: As a large amount of exhaust gas enters, the engine will misfire slightly.





7. REMOVE VACUUM GAUGE
- Remove the vacuum gauge, and reconnect the vacuum hoses to the proper locations.
8. INSPECT EGR VALVE
- Apply vacuum directly to the EGR valve with the engine idling.
- Check that the engine runs rough or dies.
- Reconnect the vacuum hoses to the proper locations.
9. REMOVE SST FROM DATA LINK CONNECTOR 1
SST 09843-18020
IF NO PROBLEM IS FOUND WITH THIS INSPECTION, SYSTEM IS NORMAL; OTHERWISE INSPECT EACH PART