I just bought a 2010 f150 4.6 3valve with 14000 miles on it. The ac compressor makes a ticking noise and the motor sometimes runs alitte rough at idle with the ac on.any sugestions. With the ac off it idles fine and there is no noise.

 

Is it a clicking behind the dash

 

No the compressor it changes with rpm

 

But with only 14, 000 miles I cant believe the compressor would be bad. The ac blows cold.

 

What is that clicking sound behind the dash? I assumed it was a relay of some sort. I didn't think much about it until I looked at this thread.

 

It's a part that goes to the AC temperature gauge. It usually click when you turn on the AC or change the temperature. There is a thread on here explaining it better with pictures of the part. Unfortunately I cannot find the thread. I am going to have my dash taken apart tonight and will take a photo of the part.

 

Bump