Is the belt slipping?

 

You may have a fan motor with the bushings out causing the blade to wobble. grab the blade and see if you can wobble it around. it may be that while this fan doesn't run all the time while you are driving faster than 35 mph (unless you are using the ac) the air passing through the blades make it spin and make noise. i had one that would squeal like a siren when i got over a certain speed and it boiled down to a bad bushing in the cooling fan.

Keep us updated when you finally find it.

 

The fans are electric and completly separate from the engine driven components. I do not believe the belt is slipping, I'm not saying that its not slipping but it doesn't make the classic slipping belt squeal

 

mrfixit's post suggests you check the fan motors. He knows they are electric.

As for a slipping serpentine belt, check to see if any of the pulleys are hot. Also check the tensioner and make sure it's set properly.

 

Got it, thanks! I'll go out and check the fans right now. Could a bad cooling fan cause the ac fan speed to vary? I suppose if it's an electrical amperage fluctuation it would be possible huh? I'll be back with my findings!

 

Ok here's the latest. I checked the electric cooling fans and neither one felt worse than the other. They both felt tight as far as forward/backward movement along their center shafts and neither of them had side play. I turned the A/C on and ran the RPM's up and down manually with the throttle body and never got it to make the noise. Then I took it for a quick drive down the block and on the way back it finally made the noise. The noise was very much like a "groan". It began to do it pretty consistently, about every 3-5 seconds so I parked and raised the hood. It's louder on the passenger side closest to the firewall and I can physically feel vibrations in the A/C lines, not the cold line but in the hot line and a lot of vibration in the dryer. I held a long screwdriver against the compressor but didn't feel anything other than engine vibrations. Does this ring a bell with anyone?

***Everything seems to be securely mounted too and nothing appears to be rubbing anywhere.

 

Just guessing but maybe you have too much refrigerant in the system. The only way to besure about the quantity of refrigerant is to have it all pumped out and then put the right amount back in.
Not sure about how that relates to the other symptoms unless the compressor is completely stalling out and stopping the drive belt.

 

I'm going to take it to the A/C shop Monday and have the system serviced. I'm keeping my fingers crossed that will fix the problem! Stay tuned!

 

Hey all, sorry for the delay. Things have been crazy at work. Anyhow I wanted to give you all an update, I took the car to the A/C shop and he hooked it up to his machine. It was within one ounce low of being fully charged but he went ahead and vacuumed it out and refilled it anyway. After that the noise is completely gone! I have no explanation as to why or how but it is gone. I have been having an issue of the A/C blowing nice and cold then it will suddenly blow only cool air, never warm as if the compressor was turning off, Just cool air. I thought I would be back in the A/ C shop but then I decided to put it on defrost since the compressor runs in that mode and sure enough its nice and cold all the time. Apparently I have a blend door problem but for now the defroster is working just fine at cooling the car down.

Thanks to everyone that's offered their input!

 

Thanks for the update. I don't know what kind of machine that guy has that can weigh freon in the system, but it will be welcome news to the people at Chrysler who wrote the service manual and stated that there's only one way to be certain of the quantity: pump it out and put the right amount back in. Funny how actually doing that fixed the system...
Anyway, I have had the same problem with the system reverting to "defrost". That's fine in the summer when you just want cold air and can live with it coming from wherever but when it happens in the winter, that cold air ain't so great. It seems to be a control head problem. Replacing the controls has (so far) cured my problem. We'll see how well it works come winter.
Controls for this car are common with Sebrings and Dodge Stratus over a six year period, so there are lots of them floating around. They come up on eBay regularly and aren't very expensive. Installation is literally a snap. Pop it out and unplug it, pop in the new one. If the bezel doesn't match, you remove a few screws.