Hey guys.
This problem just started today on my 2002 Ram 1500 with the 4.7L
I've searched the forum and internet, and see a lot of people with the same issue, but not many answers.(that I could find)

The AC works great as long as the truck is moving. When I come to a stop, the fan is still blowing fine, but after a few seconds, it starts blowing hot air.
As soon as I start moving again, it gets cold again within a few seconds.

I've seen people say it could bea bad compressor, the wrong resistor, vacuum leak, or simply low on freon.

Curious if anyone has had this issue and found out exactly what it is.

Thanks for your help.
Ken

 

Check to make sure your condenser fan is working. Its possible that the air blowing across the condenser is doing enough of the work when your moving but when stopped and no air flow across it it could be overheating...

 

X2 what HansonHVACsaid.

Look at my recent post "ACproblems" about my AC fan condenser woes............[:@]
Al.

Link to post:- https://dodgeforum.com/m_978740/mpag.../tm.htm#978740

 

+3

warming temps at idle is also consistent with low freon. If the level is low, expect to hear the a/c compressor cycling a lot. It's easy enough to check with a set of guages, and usually that's the first thing you do when trouble shooting a/c issues.

 

sounds like the condenser fan ... had mine replaced for the same problem ... cost me about $450 [:@]

 

Thanks a lot guys. I'll check the condenser fan and freon.

 

NNNNOOOOO Hooking up guages is the LAST think you do when troubleshooting. Everytime you hook up your guages you loose a lil bit of refrigerant no matter what. Anyone that knows what they are doing can usually get a really good idea if its undercharged without hooking up gauges anyway.

 

Well, I went out there and took a look real quick. You guys are right. It appears to be the condenser fan.
The #39(condenser fan)fuse was blown. I don't have any spares so I gotta run up to get some.

It would be nifty if I just stuck a fuse in and it worked great, but I assume the fan has an issue otherwise it would have not blown the fuse in the first place.
The blades did turn easily with my fingers so its nothing too obvious.

My buddy has an older 1500 and has the exact same problem. He's went to 2 different AC places, and they all scratch their heads on it, replace his freon and the issue remains. He's gonna be mad when he finds out he's been sweatin the last 2 months and all it would havetook was 20minutes on this forum!!

 

Hey Ken. I had the exact same issue with my A/C. Cold while driving hot at idle. Ended up that the clutch assembly on the compressor malfunctioned and would be engaging/disengaging while at idle but was fine at speed. Dealership replaced the whole compressor so I would assume that the clutch is not a separate part. No matter, it was warranty work. How many miles on your rig? I think mine went around 80K.

 

Had the same problem when I had my '02 it was the condenser fan once and the fuse about a year later changed the fuse and didn't have any more problems.