06 Vue v6 having AC issues
 

I recently bought an 06 vue v6 with 100k miles ish. I love the car and the fact that I got it for so cheap was great. The features it has makes up for the cheap plastic and it rattles when I'm going 70+ mph but I don't really care about that.The one thing that gets me is the AC. It kinda works ish, where it blows just coolish air on all vents except the passenger one(works fine). It blows colder air the more I "drive" it, specifically, when I'm stepping on the gas pedal. I have been given quotes of around $90-150 just to diagnose the problem so I wanted to hear what you guys think before I do so. P.S., it's an automatic non AWD

The system likely has developed a leak and is most likely low on refrigerant.

You don't know how the previous owner dealt with this. Maybe tried recharging and this is the result after x months; maybe tried nothing at all.
It can't hurt to ask about the history of the AC in the vehicle.so that you don't spend extra money finding out something that is already known.
The worst you get is "I don't remember".

The fact that you have some cooling going on says that the system has enough refrigerant to let the system run and that the compressor is somewhat functional, though its health is unknown.
Increasing the engine rpm increases the speed at which the compressor pulley is spinning and naturally causes the compressor's performance to increase.

If you are low on refrigerant, once you get down below a certain amount, the system has a low-pressure switch that will inhibit the compressor from turning on, so you probably want to get this addressed now vs mid-July or August.
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You need a gauge set for Automotive systems that reads the HI and LO side pressures with the system running and not to see how the system is operating and whether it is adequately full of refrigerant.
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Everyone is quoting you for a diag fee to look at it.
If low, some may recharge it and see what happens as a function of time.
Some may add UV dye and charge you to look for the leak in the system. Sometimes it's an o ring, sometimes it's a pinhole in a component of the system that is difficult to remove and $$ to replace just the part, making the repair financially not worth it.

If you're automotively inclined or have a friend that understands automotive AC systems, work with them. You can usually get a gauge set via loan a tool at Autozone.4

If you have no real idea what I'm talking about above, leave it to a pro.

Just remember: 12 year old vehicle. Parts and labor to replace condenser, evaporator, compressor =$$ vs "charge and see" (if appropriate).
The gauges should read APPROXIMATELY 225 HI and 25 LOW @ 2000 RPM, and the low pressure reading should be in the vicinity of the ambient temp with the system not running.

Wow, you gave me a lot of food for thought. I just contacted the dealer they wholesaled to the dealer I bought this vue from to see if they have any notes or something like that. I'd go and complain but as is, is as is.I also have a buddy who's really mechanically inclined. I'll ask him sometime this weekend to do this AC thing. Thank you so much for giving an in-depth answer with suggestions and stuff. Thanks once again!

Geez, after derfs detailed explanations, I kind of hate to make this suggestion, but am going to anyway. Check the belt tension around the ac compressor. Sometimes a loose belt can cause problems. Higher rpms kind of "tightens" it.

Ain't nothin wrong with chiming in, Rube. I'd much rather it be something like that.............

Probably the control valve in the compressor is bad. $25 and an hour labor, but most shops have no ideal about it and just want to replace the compressor and hand you a $600 bill.

https://www.fototime.com/5105551C345EE39/large.jpg

How is this valve supposed to work (correctly) and how does it fail?
Do you need specialized tools to replace?
(obviously, I like learning new stuff)

Not really sure how it works. There is a rubber seal around it like a piston ring which I assume wears. Just hand tools to replace.

Scroll valve
 

the Scroll Valve has a tiny hole in it that clogs and fails notoriously. I agree with you this is the problem 99% of the time on this vehicle years 2002-2007

There's one necropost I actually don't mind.

Thanks for closing the loop on that one