Hello all. I have a very nice '04 F150 Lariat Crew cab. My family and I love this truck. I bought it used and was told that the previous owner remported intermittent problems with a/c not being cold. I drove it alot before I purchased it and didn't detect any problems. Now I do. Sometimes the a/c simply doesn't come on. I don't hear it come on and don't detect any change in my idle speed that I would expect when the compressor comes on. Sometimes, I'll leave it in the on position and mysteriously it will start working for no apparent reason. I am writing now because I have noticed...(well my wife brought it to my attention) ... I have noticed a similar problem with the heat. It was about 20 deg/F and I had the climate control set to 75. The air coming out was cool at best. I ran teh tmep setting up to 90 with no change. Again... 30-40 miles down the road it started blasting BTUs and I had to set it back to about 69. NOW, the other day I wanted a/c and it wouldn't come on. Considering the problems may be related, I tried to turn the temp up to 90. I could not get the air temp from the vents to change temp in either direction, hotter or colder. Any thoughts? Thanks for reading and for any thoughts you may have!

 

Have you found the solution?

 

Just last week an expert mechanic foiund a loose wire in a plug to the A/C. It's working great. NO clue on the heat though. I had hoped for obvious reasons that they were related.