I have a 2004 f150 with the automatic adjusting heat. When I turn it on, it goes all the way hot. I can start it in manual and I can only get full hot. I can turn the AC on and I still get full hot air. I can adjust the fan speed and switch the location I want the air to come out but I can't adjust the temperature. Any suggestions?
Thanks for Any Help

 

I don't know what Ford has but other vehicles will have 'blend door actuators' that can fail and cause this and other problems. Typically, they are not that hard to replace although the dealers will charge $500.

 

Combined with your other post, it sounds like a vacuum issue to me.

 

I went by O Reily's and got a blend door actuator but after looking at a couple videos, I'm pretty sure it's not the right one. All the videos I've looked at show one with a long shaft and this one has a short shaft. Here's a little more on the heat situation. I have found that sometimes when I turn the AC on (it has the climate control heater) that I get cool air, not cold but cool. Yesterday, it did this for about 3 min max then I heard the blend door move and it went to putting out hot, hot air, Today when cranked it after it had been sitting overnight and most of the morning, I tried to do exactly as I did yesterday but I had no cool air at all, if any, very little, and went straight to hot. This is with the temp set to 60 degrees, as cold as I can set it. I did notice the AC compressor is not running. The blend door is definitely changing from AC to heat on it's own. Would the actuator do this. Would some of you guys or gals that are familiar with these heating systems give me a little guidance as how to diagnose this problem. I'm 73 years old and have always done all my mechanic work but mostly what I've worked with have been manual, on/off switch type of units, I have as little trouble sometimes getting the working order of some of this stuff in my head. I just bought this truck because it had a super good body but seems like it's having a lot of little problems come up.
Thank You for the help

 

One other thing, CathedralCub seemed to think I may have vacuum problem. Vacuum is not used for any of the heat controls on this model are they?

 

no... all driven by motors, older trucks used vacuum. there's foam around the blend door that is a common problem, it come detached and causes the door to get stuck.

 

Ok, here's the latest. I had a little time to work on it today. I charged the AC. The tag under the hood calls for 34 oz. I have put 36 in it and still have only 25 psi on the low side and about 110 psi on the high side. They fluctuate a little from that to a little higher. The compressor runs all the time and it's putting out 140 degree air inside. I did lower the glove box and a section of the heater box to the right of the blend door actuator', about in line with the left side of the glove box is real cold so by that I would say the AC is working. As I mentioned in the earlier post, usually after the truck has been sitting for a while I can turn the heat on to 60degrees and it will sometimes blow cool air, not cold but cool for a while then goes hot without me touching any settings. I did have it to blow cool air probably 30 minutes or so the other day but when I got home with it and switched it off, I cranked it right back up and it blew hot, didn't touch the controls.
What's some of you guys opinion on this. I'm tempted to put a blend door actuator in it but I really don't believe it will fix the problem. Could they work part of the time and not work the rest of the time?

 

Problem solved. Installed a new Main heat door actuator and if solved the problem. Someone had replaced it before with one that had a snap-in shaft and it had become un-snapped and fallen down far enough the actuator wasn't catching it when it was trying to turn it. I don't understand why it would be made to snap in or out anyway. I guess some of those quality replacement parts. Now on to my next problem which I will be starting a new thread on shortly, the overdrive shudders.

 

Just thought the problem was solved. It throws a code showing there is a problem with the Cylinder Head Temperature Sensor. Does it work the temperature gauge in the instrument panel? It fluctuates from cold to operating temperature. The engine will idle fast sometimes when it shows a cold temperature reading. Also, the AC will blow out hot air when it drops to cold temperature reading. I have had the problem of the engine misfiring when shifting to overdrive but I wanted to fix this Cylinder Head Temperature Sensor problem before starting on the misfire in case it was causing some of that problem. Any advise on changing and checking the Cylinder Head Temperature Sensor?