New to MustangForums, so I hope I'm in the right section. Just got a 2011 3.7auto in June and although I love it so far, I've got an interesting problem.
Air works just fine until I take it on a trip that lasts longer than 3 hours. First noticed it at the end of the first half of a trip when the cool air seemed to become warm air !! & chalked it up to me pushing too many buttons at one time on the a/c controls, since the next time I started it up after sitting for a few hours, I get full a/c.
But, surprise, surprise, on the second leg of my trip and getting close to my home after 3 or so hours, the a/c once again gave up the ghost and just started blowing air that was not cool [ and that is not cool !! ] since it was about 35C outside. Again after reaching home and unpacking and then starting the car after about an hour, the a/c is fine.
Brought it to the dealer and since the a/c is working fine, he thinks I'm nuts since he can't pull a code. Oops. Now he tells me to drive for as long as it takes to cause the problem and then bring it in. Okay.
Thoughts?

 

You might want to consider driving long enough to allow the problem to rear it's ugly head if you want it fixed. Oh, wait. That's what the dealer recommended.

How else do you expect the dealer to reproduce it? Do you want one of his grease monkeys to take it on a 3 hour cruise? Work with them if you want it fixed.

Are you sure you have the temperature turned to as low as it'll go?

 

Will work with dealer as requested but was wondering if I was the only guy with this problem so I can avoid taking a long trip to try to reproduce this.
Hadn't touched temp control, both times this happened. This loss of cold air doesn't happen when driving around town, which is 95% of my driving.

 

Had the same problem on the wife's 2001 Taurus a while back. Couldn't reproduce it at the dealers. Yeah, just drive it around till it happens again, then drive straight to the dealer, pull up in front of the service guy and leave the car running so he can see for himself. Even if they can't take it in right away, you have it on record.

Cheers.

 

My 1999 Trans Am did the very same thing, and the dealer never found out what the problem was. It pissed me off on long trips, especially in the hottest months of summer.

 

Intermittant problems are a biatch for techs to diagnose.
I have had the chally in 3 times when the window would
not short drop or roll down.
When I arrive at the dealer asap, the problem wont show itself.
They wont fix it until they diagnose it and when it decides to
work 100% at the dealership, what is one to do?
But when you open the door and the window does not short drop
and wont go down with the window switch, what do you do?
Slam the door anyway and fork up the window and rubber trim
that is designed to work with a short drop glass?
I finally BOUGHT a new motor/logic controller and replaced
it myself on my own dime despite being only 6 months old.
I feel for ya.
I would bypass the pressure switch next time this happens
and see if the compressor clicks back on.

ps the compressor clicks off at WOT regardless of the A/C control settings

 

Nemosgt... got a sneaky suspicion I'm gonna have to do the driving bit.

Unleasedbeast.. I can't even begin to imagine what you had to go through in Florida weather compared to here in Toronto.

157dB ... assuming Ford is still using the same a/c system for the 11 stang, where would the pressure switch be located, relative to the compressor? Does this bypass involve just using a jumper wire? Bear with me here, electrical gremlins have been my master for a long time.

 

Evap freezing up due to bad TXV (Thermostatic Expansion Valve)

 

It mostly happened on long drives at night on the interstate, and normally about 1.5 hours into the drive. I would turn off the A/C, roll down both windows, sometimes remove the T-Tops, and drive faster.



It really sucked in August and September. 98-102* temps are common during the mid to late afternoon, add in humidity and your heat index is easily 115*

HAWT!!!!