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Home >> Plymouth >> 1978 >> Arrow Base, Automatic Trans >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Exhaust Gas RECIRCULATION >> Testing >> EGR System Test >> 1976-77 Models
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1976-77 Models

  1. With engine cold, start engine and allow to idle. Increase engine speed to 2500 RPM and place finger under EGR valve to check operation of diaphragm.
  2. With engine coolant temperature below 104°F (40°C), the diaphragm should be stationary. If diaphragm moves, Green stripe vacuum hose is clogged or thermo valve or EGR valve are defective.
  3. Warm engine until coolant temperature exceeds 104°F (40°C). Increase engine speed to 2500 RPM and place finger under EGR valve to check operation of diaphragm. If diaphragm moves, EGR valve is okay. If not, Green stripe vacuum hose is clogged or thermo valve or EGR valve are defective.
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