Groaning noise when AC is turned on.

[DoThisMyWay]

The Car: 2005 A4, 3.0 Quattro Tip, absolutely and completely stock with 68k miles.

I’ve searched but can’t find anything quite similar to the loud groaning noise when the AC is turned on. The noise lasts for about 10-15 seconds and disappears. On cold starts, the noise is louder than when the car is already warm and has had the AC running previously. The AC works and produces cold air. It’s just the noise I’m concerned about. Otherwise, when the car is started and the AC is not turned on there's no groaning noise, just the usual lifter chatter.

Any help is appreciated. Thanks!

[TrojanRings]

I had this issue (it seems similar) a few years ago: http://www.audizine.com/forum/showthread.php?t=98474

It ended up being a seized A/C compressor. Hope this helps.

[DoThisMyWay]

Did your AC eventually crap out and quit working?

[TrojanRings]

No, luckily it didn't get that far. I guess the bearing was on its way out but hadn't completely seized yet. I had the stealership look at it when I brought the car in for its scheduled maintenance. It was covered under warranty.

[audinaut]

Check the A/C fan. You have two fans in the front of the car -- the A/C fan is the passenger side fan. Pop the hood, turn the car on, turn the A/C on. If the noise only happens when the fan is running, the motor bearings in the fan are going bad. If it is the fan motor bearings, the noise will not be heard when the fan is not running. If it's the fan motor bearings, the groaning noise will become more pronounced and be present longer when the fan is running. Cheapest place to buy a new fan with motor is GAP -- wrecking yards quoted me about $50 less then a new fan from GAP. Unfortunately, the way the fan motor is assembled, it is difficult to address the bearings only. Fan can be replaced easily on the car without taking anything else off. I replaced mine at somewhere north of 50K miles because the fan motor bearings went bad. Symptoms were the groaning sound after initial start up of the fan with the groan disappearing. Over time, the groan lasted longer before disappearing until it eventually it was constantly present during motor operation.

[DoThisMyWay]

^^Thanks to both! I'll have to check the fan out. What's GAP? GermanAutoParts.com? I really don't want to take the car to the dealer if it's something I can fix myself.

[TrojanRings]

GAP = http://www.genuineaudiparts.com/

[DoThisMyWay]

Cool, thanks!

[audinaut]

I really don't want to take the car to the dealer if it's something I can fix myself.

If you're under warranty, by all means have the dealer replace it for free. If you DIY, the Bentley may tell you to remove the entire front end including carrier (I can't remember exactly, it was a few years ago that I replaced mine). After looking at it, I figured that I could just take the fan out without going through all that. IIRC, I had to remove some other hoses and wires as there was some clearance issues with the tight space restriction, but I got it out and the new one in pretty easily.

[DoThisMyWay]

I got a chance to look under the hood while the AC was turned on and the noise doesn't seem to come from the either fans but more or less from the actual compressor area. I'm out of the normal 4yr/50k warranty but I do have extended warranty to 100k, so I guess I'm going to have to go to my dealership to see what my options are.

[audinaut]

Good thing that you have extended warranty. Replacing A/C parts can quickly become expensive. FWIW, routine maintenance of the A/C system can help avoid costly repairs in the future. The A/C refrigerant carries the oil that lubes the compressor -- too much or too little refrigerant is not a good thing.

[DoThisMyWay]

Just an update of this issue… Took my car in 3 weeks ago and service told me the noise disappeared. I brought the car home and what do you know, it still made the groaning noise. Took the car back today and they're replacing the AC compressor. So, in the last month I’ve had the steering pump, AC compressor and some cracked suspension bushings replaced for about $2300... Thank goodness for extended warranty!

[Rockclimbersh]

no extended warranty here. i just dropped 1350 on a new compressor and dryer unit... sucks.

[DoThisMyWay]

^Sorry to hear man... My B6 has been something else these days. I just hope nothing serious happens to my B7 because I'm completely out of warranty on that one.