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1976-78 Models (Except RX7 Man. Trans.)

  1. Disconnect vacuum tube from trailing vacuum control unit of distributor. Disconnect water temperature switch and connect a jumper wire to both connector terminals. See Figure.
  2. Start engine and set engine speed at 2000 RPM with choke knob. No vacuum should be felt at vacuum sensing tube. On Federal models, push choke knob in fully. Suction should now be felt at disconnected trailing vacuum tube. On California models, suction should be felt 104-156 seconds after starting engine.
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