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Thermostatic Air Cleaner: Testing

  1. After engine has cooled down, start engine. Check position of air control valve and observe valve as engine warms up. Check to see if the heated air intake port is fully closed at an underhood temperature of above 108°F (42°C). If not, replace air cleaner snorkel and/or casing.
  2. If equipped with vacuum motor, apply 15 in. Hg to motor while engine is cold. Air valve should be up (heat on). If not, or if valve goes down immediately, a vacuum leak or defective motor is indicated. Replace assembly.
    Fig 1: Thermostatic Air Cleaner
    G09313054Courtesy of CHRYSLER GROUP, LLC