My car just returned from being at the dealership for 2 weeks and here is the solution and what to watch out for:
As many of you know, I am probably anal about noises in my car just as much as Aaron is about scratches in his. So I hear things that others don't. I was hearing the a/c noise when others were not. In fact many times I would ask others to listen to it and point to the noise and they would not hear it. The dealership that I normally go to (Ann Arbor Infiniti dealership) I asked a mechanic to sit in the car and listen pointing out the noise and he said it was so faint that that is normal or couldn't hear it.
I kept hopping from dealership to dealership until the dealership at the Suburban Infiniti in Novi said that it sounds like a bad compressor and they replaced the compressor. After I got it back the problem was still there. Like I said, those people driving 2009-2012 definitely have this problem it's just a matter of if you are a person that hears it or not since it is so faint but over time it will get louder and louder as you put on many more miles to the point then it becomes an expensive problem so it's best to get it resolved immediately while under warranty.
When this bulletin came out, I went back to the dealership and they ordered the part based on my vin #.
After the install I didn't hear the noise, but after many miles I started too again. Then after probably 15,000 more miles I noticed recently my a/c was not blowing as cold air as it was when it had 25,000 miles.
I brought it to the Ann Arbor dealership this time. Here is what they found:
There are numerous versions of the hose replacements for this. The vin # does not help insuring you get the right part. The problem is due to the fact that Infiniti corporate has created a ton of compressor versions throughout 2009-2012. And I'm not talking about 1 for every year, but multiple for every year. The version numbers are the same but they differ by ending in A, B, C, D, and so on within the same year I believe. I was at a cutoff point between version A to B to C of the 2009 model year. Each requiring a slightly different hose for the fix. Each slight compressor difference requires a completely different hose or different part of that hose to be replaced.
Why the big deal?
Well since the wrong hose version was put on, it actually completely ruined the compressor and all the freon had evaporated out of it. It was all due to the hose and how it was installed. So it required not just correcting making sure the right hose was replaced this time, but also a new compressor since the slightly wrong hose caused it to fail over time. Ann Arbor knows how particular I am so they were on the tech lines with Infiniti corporate several times to insure I get the right updated hose and compressor. Even the bolts for the compressor for each compressor models are different! That is why it took 2 weeks. They kept overnighting parts and each time would get the wrong version even based off the vin. Every time something didn't fit like "butter" the tech lines at corporate were called by my dealership and sure enough they were sending wrong parts time after time. Again, this is what makes a great dealership from an ok dealership. They sent back and overnighted parts numerous times because there are so many versions of them with the same number.
So now what?
The FX50S has a new correct updated compressor and the new bulletin hose (the right one for that particular compressor). NO NOISE AT ALL.
1. If you hear ANY noise, get it fixed. You are going to have problems later.
AND
2. Make 100% certain they are getting the right hose. If it's not the absolute right version, you can have a $2,000+ repair coming if you are out of warranty. A great dealership and great mechanic are key here. Vin # is not enough. If the piece does not fit like "butter" to the mechanic, then it's the wrong one and you will have big problems later especially if you don't have a warranty! Luckily I have 100,000 mile warranty that came when I purchased the car. Even the first tech line at infiniti apparently was wrong and it was only after they asked for higher level support on the tech line did they finally sort out the mixup between all the versions within the same year periods that our cars have I didn't know Infiniti is constantly updating parts along the way as the cars roll off the line, but it's scenarious like this that you then later have to make sure the mechanic makes the proper contacts at Infiniti tech lines to make sure you are getting the right replacement parts for the particular date of when your car rolled off the factory line.