AC Compressor Stops while not moving

2003 Dodge Ram 1500, 4wd 4.7L V8 - approx. 2 years ago the AC stopped blowing cold when not moving. It actually felt like heat. Dodge service concluded 134a was a tiny bit low, but even topping it off to the standard 1lb 10ounce didn't do the trick. No leaks to speak of and off I go with them shaking their heads.

Noticed that the compressor cycles about 6 secs on and that's it (while stopped). Several suggestions were clogged orifice tube (not sure where it is on this truck) bad clutch fan or leak/low refrigerant. Temperature gauge never really fluctuates and while driving the AC seems to be operating well, but not totally up to what I would say is quite as cold as normal. Most people don't notice so maybe it's just me.

Any suggestions, links, schematics, troubleshooting steps would be much appreciated.

Reply to
wolfe6168
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fan clutch. try wetting the condenser with a hose to see if your cold air comes back

Reply to
Steve Austin

I'm curious as to how much the AC control is integrated with the engine management system. If it is pretty much independent, I'd say that you have inadequate air flow over the AC condensor and the high-side pressure cutout is tripping. Check for a weak engine-driven fan clutch or an electric fan that isn't working.

If its more integrated with the engine management system, it could be the computer shutting it down at idle for some reason, whether valid or not. Does dropping the transmission into neutral and revving the engine to 1500-2000 RPM while sitting still restore the cool air?

Reply to
Steve

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