I turned on my AC today and it wasn't quiet like I remember. I could feel a vibration in the steering wheel. It blows out cold air so it works ok. The vehicle only has 34,000 miles on it so I find it strange that it's starting to act this way. Any ideas on what it could be?

 

If we knew what year and motor you have that would be helpful.
First, with the engine off, check to see if the drive belt is loose or contaminated with oil or coolant.
Next, with the engine running and your vibration present, turn off the a/c. If the vibtation is gone, check the mounting bolts to the compressor ( any loose?), if you still haven't found loose bolts, it's probably a worn bearing in the compressor clutch.
Then you are looking at a proffessional repair.
Good luck, hope this helps.

 

I suspect an IAC (idle air control) valve issue. The ECM is supposed to open up the IAC to maintain idle speed when the A/C activates. If the IAC is stuck or just not responding, you can get a lower than desired idle and a vibration as a result.

 

The car is a 2003 Blazer, 4.3L engine, and as stated, only has 34,000 miles. The vibration goes away when I shut the AC off which is why I suspect something with the compressor. It's going back to the dealer for a different problem (still under warranty). I will tell them about the AC. I was hoping to go there with some information so that they don't tell me "OH, that's normal". I know what's "normal" for my vehicle and this definately is not! I will check the belts and look for loose bolts. Other than that, I guess it's in their hands (scarey thought!).