System Testing: EGR

1. Ensure modulator filter is clean and in good condition prior to performing test. Clean filter with compressed air if necessary. Disconnect vacuum hose from EGR valve.
2. Using a "T" connector, connect a vacuum gauge in EGR valve line. Check that engine starts and runs at idle. This ensures proper seating of EGR valve.
3. The BVSV, TVSV, VSV and EGR modulator can be checked with engine coolant below minimum temperature and specified engine RPM in accordance with application. See EGR SPECIFICATIONS  table. Different valves are used depending on model. See Fig 1 through Fig 16 .
4. Operate engine with engine coolant below minimum temperature and specified RPM. No vacuum reading should be obtained when operated with engine coolant below minimum temperature.
5. Operate engine at normal operating temperature and specified RPM. See EGR SPECIFICATIONS  table for specified engine RPM. Low vacuum reading should be obtained.
6. Vacuum reading of 2.6 in. Hg should be obtained on Cressida and Supra models. On Cressida, Land Cruiser, Pickup and 4Runner (3.0L) and Supra non-turbo models, check that no vacuum is shown at idle. Also check Corolla models with EFI, Corolla FX-16 and the MR2 models at 5000 RPM. No vacuum should exist.
7. Disconnect hose from the "R" port of EGR vacuum modulator on all models except the Celica 4WD, Tercel Wagon, Pickup (turbo) and Supra (turbo) models. See Fig 1 through Fig 16 .
8. Using additional hose, connect "R" port directly to intake manifold. High vacuum reading should be obtained at specified engine RPM. See EGR SPECIFICATIONS  table.
   NOTE: Engine should misfire due to large amounts of exhaust gas being injected into intake manifold.
9. Disconnect vacuum gauge and install vacuum hoses. To check EGR valve, apply vacuum directly to EGR valve with engine idling. Engine should run rough. If system did not operate within specifications, each component should be tested. See COMPONENT TEST