hey, i have a question about the what hell my car's doing. i know it has to do with the AC unit, but i'm not sure what's wrong. the AC works great, it's powerful and cold, but when i turn it on, there's an annoying sound coming from under the hood. i checked it out tonight when my car was running, and on the AC unit under the hood (i'm not sure what it's called, i think it's the condenser), on the front of the unit, there's a kind of disc...the disc would spin for about 2 seconds, producing the noise, and then it would stop spinning for about 5 seconds, then start up again....i don't know if i have to worry about it or not, the AC's working fine, but the noise is really annoying, but most importantly, when i'm tryin to show off my car, havin a very noticeable noise coming from under the hood is kinda embarressing. so any help with why this noise is occuring, and if there's any way to fix it w/o replacing the whole unit, would be appreciated, thanks yall..

 

Sounds like the compressor is about to go. The condenser is the part in front of the radiator.

 

That unit with the spinning disk is the compressor.

The condensor looks like a radiator and sits in front of the real radiator.

The compressor has a clutch. When the disk is spinning, the clutch is engaged.

There's a low pressure switch mounted to the accumalator (also known as a reciever/dryer). Its the big shiney thing on the pass side of the eng compartment near the firewall.

If the freon press is low (as in it has a leak), the compressor clutch will engage for a couple of seconds.
The "low" side of the system gets lower when the compressor clutch engages.

The low pressure switch will see the low press condition and dis-engage the clutch to prevent damage to the system. Pressure will build again and the cycle starts all over again.

If you are running the A/C system with a low load (I.E. fan on low, outside temp low), the compressor clutch will cycle more frequently. If your running the fan on high and the outside temp is high, the clutch shouldn't be cycling.

If the compressor makes a lot of noise while the clutch is engaged, it's probably in need of replacement.

Until you get the A/C system fixed, select the A/C-heater controls to a position other than a/c, max, or defrost while showing-off the eng!

 

so what about if i put it on heat but put the temp control to cold? i could go check but it's a loong walk to where my car's parked so since it seems like my condensor is going out, while i'm runnin it one day will it just shut off for good? about how much would it cost to replace a condenser? if it's too much, i might just go ahead and take the AC unit out, who knows...or i'm prob. selling my car this summer to get a better one, so the condition of the AC won't matter as much to me...thanks

 

That will work..
The compressor only runs when the A-C/heat control is set to A/C, max or defrost. All other positions (off, vent ,heat) do not use the compressor. The "hot-cold" lever has no effect on the compressor.

If your compressor is making a loud knocking sound, it's not going to last very long.
It will eventually stop pumping freon and then won't work at all.
I got my compressor replaced and converted to 134A refrigerant for $500 a few years back, and I got a pretty good deal.
Expect to may at least that much, probably more.

How hot are your summers?
Around here, when it's 100+ degs, it's damn hard to sell a car with no A/C.