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Home >> Jeep >> 1981 >> Pickup J20, AWD >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Exhaust Gas RECIRCULATION >> Testing >> EGR Valve >> Valve Opening Test
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Valve Opening Test

  1. With engine at normal operating temperature and at curb idle, rapidly open and close throttle (open throttle sufficiently to obtain at least 1500 RPM). A definite movement should be noticed in the EGR diaphragm.
  2. If diaphragm does not move, probable causes are: faulty vacuum signal to EGR; defective EGR diaphragm or defective back-pressure sensor diaphragm (if equipped); or leaks in vacuum lines or connections.
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