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

  1. With engine at normal operating temperature, remove dump valve vacuum hose from manifold and plug manifold connection.
  2. Accelerate engine to 2000 RPM. Vacuum should be present at exhaust ports on bottom of valve. If not, replace valve.
  3. Reconnect vacuum hose to manifold and accelerate engine to 2000 RPM. No vacuum should be felt at exhaust ports on bottom of valve. If vacuum is present, replace valve.
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