Not sure if this is Mechanical/Electrical or "USER ERROR"

[denalimike]

Hello,

I have had issues with the A/C going in and out recently. To start off, when driving for an extended time, I noticed that the A/C would have a faint "watercooler/swampcooler" smell and it would just blow hot air. I took it to a shop I use from time to time and the guy said, it's possible that the water level is low and so he proceeded to fill up the water tank. (Which seemed like it was enough water to make a difference) Well, it fixed the problem or at least I thought it did as the A/C was working. Later I realized that the A/C kicks on and off as I drive in "city traffic" whereas if I am driving on the Highway, it doesn't work at all. If I am parked, even after driving a while and the truck temperature being elevated, it kicks back on as if there's no problem. Anyone familiar with this problem?

Thanks!

 

[Doubeleive]

 

[Scottydoggs]

got a clutch fan on your truck? it might be shot. grab a couple of them fins and push and pull it, if its moving its bad.

and its normal for the compressor to kick off and on. just like a ac in the house window.

 

[M1Gunner]

Year, make, model. Auto or manual a/c with or w/wow rear a/c?

 

[denalimike]

2005 Yukon SLT I think, not the Denali. AC is digital one, not the mechanical/manual version. New developments. I noticed when slowing down after a drive on the highway with the radio off, I could hear/feel the compressor or something kick in and then the ac started blowing cold again. I understand that the ac may kick on and off but it stays off for a long "fast" drive and i'd hate to pay for a "recharge" if that won't fix it. We are going on a trip soon so any help is appreciated. I am sorry for the delay in replying. Not sure what a clutch fan is.

 

[denalimike]

found what a fan clutch is. 1 comes with water pump. Don't have issues with overheating so do I assume that the waterpump is fine? (In the event if it's the fan clutch)

 

[Scottydoggs]

this would be a good time to swap to electric fans if the clutch fan is shot. like i said earlier, grab the fan blades and push and pull, if bad you'll feel and see it moving at the base where that large nut is. if it moves its dead. i went through 3 of them. then went with two 16 inch pro comp fans off a fog light switch with a ignition on power source, so they just ran all the time if the truck was running. you'll need a relay per fan too. my ac was never colder after the fan swap. truck ran a degree cooler too.

if you mean fast drive as in you got it floored, the ac compressor turns off when you go wot.

 

[denalimike]

I meant driving on the hwy. Do I need to take apart to diagnose?

 

[Scottydoggs]

i really cant explain grab the fins and push and pull look and feel for movement side to side, (not spinning it) any clearer.

normal hwy driving the fan should not even be a issue. the air from moving at 50 plus mph is enough to make the ac work really.

 

[denalimike]

I guess I am confused if you're referring to the fan that cools the engine or the clutch fan. I guess if the ac works while idle, the clutch fan may work though. I can be parked for 20 minutes and ac works just fine. It's frustrating because I dont want to just start buying parts that may not be broken. Thanks for your help.