Air conditioner compressor noise?

[Mark Grant]

Howdy guys. We've owned our 02 WRX since new. Car is totally stock with about 92,000. Since we bought the car the AC has SUCKED. It was so bad I took it in and made the dealer test it. They said it passed, I didn't think it should have. Am I crazy or are the AC units in our cars to small? Why do most of them seem to start locking up around 50,000???

[kjb]

I've been doing quite a bit of research on a/c problems lately and found out that a common problem on the '02 is the expansion valve going bad (happened on mine and I believe also caused a leak in my evaporator). This can cause your pressures to get wacky, which will cause the compressor to behave funny and the belt slipping/loss of power issue to occur. So before you assume it's a bad compressor, I would check your high and low pressures (this thread is a good start ) and make sure your exp valve is operating correctly.

[shello007]

I actually bought a used compressor. Took it to the Mechanic. He never looked at the 'new' one I bought. He tested the pressure and it was waaayyy!! overcharged. Released some of the freon, and presto. A/c works fine. except that it struggles to keep car cool when it's really hot out.

[03subiedude]

my car makes more of a loud squeak. i did however notice the tension mech is broke and my compressor isnt spinning and wen it does not very fast. it has a gatorback belt on it wen i bought it was makin the sound but ac worked fine. ive read these other posts and they have helped none. any advice???

[george24]

my car is making a knocking noise shortly after i start it, the a/c compressor turns on and off and starts to blow hot air, and when i turn the a/c off its stops acting weird. i also noticed condensation on my a/c vents could this be a bad expansion valve or too much pressure. i just recently replaced my a/c compressor because it was making a phhsshh noise and my a/c clutch was out, could it possibly be a bad compressor? please help if you have any info i am freakin out! (my car is an 06 sti)

[Nandn]

My 2004 WRX is experiencing the exact same symptoms as the original post. The "PSSHT" sound every minute or so and what feels like a momentary reduction in power almost like a misfire but perhaps related to the compressor turning on and off or something.

The AC still blows cold air and seems fine I just don't want to ruin the compressor and have to replace it later on or maybe the compressor is already ruined and that's why this is happening ?

Please let me know what was done to resolve this issue ? Was replacing the belt that operates the compressor enough to solve this? Sounds like an OEM belt is required to ensure fit? Or was it a faulty expansion valve ?

Thanks in advance for any help.

[Panicbutton18]

I think you'll see that whats happening is your compressor is kicking in and out thereby causing blips in your power. You can verify this merely by pulling over after the noise and subsequent power drops start occurring and opening up your hood to look at the compressor. The mechanism that attaches it to the belt should be making contact, spinning for a sec, then stopping and pulling away from the belt. I myself have not tried the expansion valve fix and probably should, but my AC, after letting some coolant out, (as I mentioned in my previous post) works well enough and long enough to where I don't have this problem anymore unless I drive long distances in hot weather I really never start baking.... My advice is to look and make sure that your compressor is the problem via the aforementioned check, then (if it is the problem) you should get a coolant charging kit... nothing fancy with dials or flashy lights or anything. Just a do-it-yourself AC charger. Then try to put some into the system.... if nothing happens, you probably have an overpressure situation and should check your expansion valve. If that is in working order, you should simply let some coolant out and see if it fixes your problem or not. Good luck!

[Nandn]

Cool [pun intended ] thanks for the heads up. I'll try that before the expansion valve. Is it true that the valve is under the dash and involves a lot of labor to get at it ?

EDIT: In case anyone cares the solution for my situation was adjusting the AC belt tension to be a little tighter. Been a couple weeks and everything is running well and no more hiccups with the "pssht" sound.