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Thermal Vacuum Switch (TVS)

  1. With the air cleaner temperature below 40°F (-4°C), disconnect vacuum hoses from TVS and connect vacuum source to large outlet.
  2. Apply vacuum to TVS. TVS should hold vacuum. If not, replace TVS.
  3. Start engine and warm air cleaner to 55°F (13°C), or greater. TVS should not hold vacuum. If it does, replace TVS.