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EGR System

  1. Using a 3-way connector, connect a vacuum gauge to the hose between EGR valve and EGR vacuum modulator.
  2. Check seating of EGR valve by starting engine and checking that engine starts and runs at idle.
  3. Check BVSV with coolant temperature below 86°F (30°C) on Pickup models. See Fig 1. Check that vacuum gauge indicates zero at 3000 RPM.
    Fig 1: EGR System
    G41560Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  4. With engine at operating temperature, check that vacuum gauge indicates low vacuum at 3000 RPM on Pickup models. Disconnect vacuum gauge and reconnect hoses to proper locations.
  5. Apply vacuum directly to EGR valve with engine idling. Engine should run rough or die. Reconnect vacuum hoses to proper locations. Engine should run smooth. If no problem is found with this inspection, system is OK.
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