Federal Vehicles (with A/T ONLY)

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 EGR valve vacuum hose as shown in the illustration.

3. INSPECT SEATING OF EGR VALVE.
- Start the engine and check that the engine starts and runs at idle.

4. INSPECT OPERATION VSV 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.

5. INSPECT OPERATION OF VSV AND EGR VACUUM MODULATOR WITH HOT ENGINE.
- Warm up the engine to above 60°C (140°F).
- Check that the vacuum gauge indicates low vacuum at 2,500 rpm.
- Check that the vacuum gauge indicates zero at idle.



- 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 will misfire slightly.

6. REMOVE VACUUM GAUGE.
- Remove the vacuum gauge and reconnect the vacuum hoses to the proper locations.

7. INSPECT EGR VALVE.



- Disconnect the vacuum hose from the 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.
HINT: As exhaust gas is increasingly recirculated, the engine will start to misfire.