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EGR System

  1. Connect a tachometer to engine. Disconnect vacuum hose 3-way connector from canister. Connect a vacuum gauge to 3-way connector between EGR valve and TVV. With engine cold, start engine and check that vacuum gauge indicates no vacuum at idle.
  2. Warm engine to operating temperature. Check that vacuum gauge indicates no vacuum at idle. Increase engine speed to 3500 RPM. Vacuum gauge should indicate over 2 in Hg vacuum. Disconnect and plug vacuum hose to EGR valve.
  3. Engine speed should increase. Stop engine, push diaphragm plate by hand and release it. Check that diaphragm plate returns smoothly to original position.
CAUTION: If valve is hot, it may be necessary to wear gloves to avoid burning fingers.