Exhaust Gas Recirculation: Testing and Inspection

INSPECTION OF EGR SYSTEM





1. CHECK AND CLEAN FILTERS IN EGR VACUUM MODULATOR
(a) Check the filters for contamination or damage.
(b) Using compressed air, clean the filters.





2. PREPARATION
Using a 3-way connector, connect a vacuum gauge to the hose between the EGR valve and vacuum pipe.

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





4. CHECK VSV WITH COLD ENGINE
(a) The coolant temperature should be below 54°C (129°F).
(b) Check that the vacuum gauge indicates zero at 2,500 rpm.





5. CHECK VSV AND EGR VACUUM MODULATOR WITH HOT ENGINE
(a) Warm up the engine.
(b) Check that the vacuum gauge indicates low vacuum at 2,500 rpm.





6. CHECK EGR VALVE
(a) Apply vacuum directly to the EGR valve with the engine.
(b) Check that the engine runs rough or dies.
(c) Reconnect the vacuum hoses to the proper locations.

IF NO PROBLEM IS FOUND WITH THIS INSPECTION, SYSTEM IS OK; OTHERWISE INSPECT EACH PART