So when my ac is on it mostly comes out the dash vents but some comes out of the defrost vents. Like 70-30 I guess. If I am not mistaken it is all controlled by vacuum. Any suggestions?
You are correct, i would check for vacuum leaks.
The nice thing is, the climate control and hubs are ALL that is vacuum controlled. My F150 had a vacuum leak that made it run like junk, took me months to find.
I hear the hub lines are a common spot for the leaks.
(Bryan) 2004 (09/2003 build) F250 XLT 6.0 CCLB:
4" MBRP Turbo back | MBRP cat "test" pipe | XDP EGR delete | ARPs | blue spring | upgraded turbo drain | homemade Baldwin coolant filter kit | Torque Pro | Glowshift EGT/fuel pres/boost 3-in-1 | SCT w/Gearhead tunes | Mishimoto rad | Ran out of room for everything else
Also, the little valve on the passenger side near the firewall behind the oil fill cap. It's black and a little bigger than a golf ball. The hose fell off of it on my truck and caused the same symptom. Easy fix. Just find the hose and reconnect it to the valve.
Search for this thread, it is helpful too. 'AC blows out Defrost'
red 04 F250 build date 04/04 6.0 PSD (retiring to farm work)
2013 gulfstream canyon trail fifth wheel Aztec edition 40 ft weighs in at 13K
Vietnam Vet/ OS1 USN/USNR retired 26 years
2015 CC f350 6.7 max tow @ 26K lariat pkg. long bed AKA big blue
Dave and Joyce
This forum is owned and operated by Internet Brands, Inc., a Delaware corporation. It is not authorized or endorsed by the Ford Motor Company and is not affiliated with the Ford Motor Company or its related companies in any way. FordŽ is a registered trademark of the Ford Motor Company.