AC no longer blows out panel; up top instead

ecline · #1 08-22-2006, 10:30 AM

I have a 2003 F150 King Ranch that has been trouble-free until now. We have had week of 100-degree + weather here in TX, and my AC now turns on initially through the panel, then switches immediately to the the windshield defrost vents up top. Whether I choose "Max" or "Auto" has no bearing on this. The only way that I can direct the air toward me is to select "Panel/Flr", but I can't get it to work like it used to and just blow through the Panel.

Any ideas as to what may be wrong with my AC? Is it just an adjustment, or is my head unit going bad? Any advice would be most appreciated.

Many thanks,
Ed

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projectSHO89 · #2 08-22-2006, 10:57 AM

Click on "SEARCH and enter "DEFROST VACUUM" for previous threads on this FAQ.

Steve

steve491 · #3 08-31-2006, 05:51 PM

This is a very common problem with a lot of different solutions. Here's my story, maybe it will help someone.
I have a 1995 F-150, regular cab, short bed, 5.0 XLT. Under acceleration the air would switch to the defrost vents, hence a vacuum leak somewhere. Every setting worked great with the exception of Max Air (regular air worked OK) so that narrowed it down to the recirculating damper. After some investigating I determined that damper was in the engine compartment next to the blower motor. That makes sense because in/out air has to be directed before the blower. The vacuum line looked good but after closer inspection and rubbing on it the line broke up in my hand. It almost resembled termite damage to a piece of wood and makes me wonder how bad all the other vacuum lines are, especially in "under the hood" conditions.
Bottom line: I repaired the white vacuum line to the servo with a piece of rubber line and all is well. Hope this helps someone with a similar problem.
-Steve-