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Cold Engine Control Pressure Test

  1. Install valve between pressure gauge and control pressure regulator. See TEST EQUIPMENT HOOK-UP  in this article. Hang gauge from convenient point above level of units to be tested.
  2. Unplug electrical connector at auxiliary air regulator to avoid overheating unit. Unplug connector at mixture control unit. Turn ignition on. Open 2-way valve for flow-through operation and check fuel pressure. See Fig 1.
  3. If fuel pressure reads too low, warm-up regulator is defective and should be replaced. If fuel pressure reads too high, regulator is defective of fuel return flow is insufficient of restricted. Turn ignition off.
    Fig 1: Cold Engine Control Pressure Test Graph
    G09326875Courtesy of NOT AVAILABLE