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Home >> American Motors >> 1978 >> Gremlin Base, Automatic Trans >> Repair and Diagnosis >> Engine Mechanical >> Auxiliary Emission Control Systems >> Spark Control Systems >> Testing >> TCS System >> Check Valve Test
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Check Valve Test

  1. Disconnect distributor advance hose from vacuum advance unit. Connect vacuum gauge to disconnected hose.
  2. Start engine. Gauge should indicate manifold vacuum. Stop engine and observe gauge. If vacuum falls off rapidly, check valve is defective.
    NOTE: A very gradual loss of vacuum is normal because of slight leakage in the CTO switch.
    Fig 1: Solenoid Control Switch Adjustment
    G09320168Courtesy of AMERICAN MOTORS/RENAULT CORP.
    Fig 2: Illustrations for TCS System Tests
    G09320169Courtesy of AMERICAN MOTORS/RENAULT CORP.
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