2008 Edge Intermittent AC Problem

[vette86]

I have a 2008 Limited (tow package) with a very intermittent AC problem.  Normally the AC works fine while driving or at idle (both fans running at idle). I'm getting approx 42 degrees out of the middle vents with ambient temp in the low 90's.  Low pressure is in the normal range. I'm not currently able to test the high side.  Occasionally at idle after approx 15-20 mins or sometimes immediately the ac will stop working, checking  under the hood I hear the AC compressor cycling frequently and see the AC fan starting to come on but cycling off and on with the compressor.  Driving the car at highway speeds solves the problem.  This is an intermittent problem as I have idled the car for 20-30 minutes and had no issues multiple times trying to troubleshoot this issue.  

 

I experienced an overheating condition one time at idle and it never returned. 

 

The current fan assembly is a non OEM fan assembly installed by the previous owner.

 

Reading on this topic I was thinking about installing a Ford fan assembly but the cycling compressor made me think something else may be faulty.  Before I spend the money I wanted to get some opinions or suggestions.

 

Thanks in advance for the help!!! 

 

 

Edited July 12, 2020 by vette86

[enigma-2]

I just ran across your post and was surprised that no one responded. Those aftermarket fan assemblies are junk. 

Did you change over to a Motorcraft unit?

 

As for the cycling, I would guess that the A/C compressor thermal protection switch was interrupting compressor operation when the fan unit failed and the compressor housing exceeds temperature limits. (It was doing its job).