1985 Lincoln Town Car AC warm air mixes with cool air

1985 LINCOLN TOWN CAR
70,000 MILES • V8 • 2WD • AUTOMATIC
Avatar
GBOITANO
  • MEMBER
  • 1 POST
My Freon pressure is fine, and the system blows somewhat cool air. However. when going up hill or accelerating, warm air comes out. Other facts:

-The cool air is never really cold it seems mixes w/warm air.
-If is set the blower to AUTO, then it will cut out when going up hill or accelerating, and warm air will seep out.
-If everything is set to OFF, then I'll still get a small blast of warm air from the heater at our feet at the top of a hill.

Is this an air temperature sensor problem, or is the intake somehow messed up, or is it something completely different? Any help greatly appreciated.
Jul 20, 2009 at 4:01 PM
Advertisement
Avatar
JACOBANDNICKOLAS
  • CERTIFIED EXPERT
  • 110,175 POSTS
The vent doors are actuated by vacuum from the engine. When you are on a hill, you press harder on the gas which lowers intake vacuum. Therefore, I think what we are looking for here is a vacuum leak. I is most likely under the dash of the vehicle, but it could even be the supply line from the engine itself. Check for broken, dry rotted, or disconnected vacuum hoses. In some cases, you will actually hear a hissing sound from them with the engine running.

Let me know what you find.
Jul 20, 2009 at 8:48 PM