2003 X5 4.4i possible compressor seizing

[X5isHers]

My wife and I were driving her car one day and it began making a noise up front. The noise sounded like the whirring of a pulley going bad at first. This noise got progressively worse over the course of about a 30min. drive. She dropped me off at work after lunch and proceeded home. I told her just to drive it home and park it and I would take a look when I got home that evening.

She called me about 15min. later and told me that the car made a really loud noise and that the steering had become difficult when it was making the noise. Work is only 6 miles from home. I told her to get as far as she could and to try to make it to the house. At this point I assumed it was the power steering pump.

She got about 6 blocks from home and the power steering completely failed and the car died. I left work to come check on the car and to try to diagnose the problem. When I got to the car I popped the hood and looked for any obvious leaks and checked the PS fluid. The fluid level was normal and not leaks were found.

I started the car and listened for noises. I heard nothing. I drove the car down the street and turned around to head back toward the house. I stopped and told here to get in and drive the car to the house and I would follow. The car died again just short of our driveway.

I ordered a power steering pump and swapped it for the new one.

Here is where it gets interesting. When I started the car after the swap, the engine made a really loud noise like a serpentine belt dragging on a pulley. She indicated that this was the same noise and then yelled for me to turn off the car as there was smoke coming out from under the hood.

I turned off the engine and checked the belts and all under the hood, all seems fine. This tells me that it is not the PS pump. I then thought that maybe it is the AC compressor. I turned the key to the starting position and turned off the AC. I then started the car and all sounded good. I thought that this solidified my assumptions. I told my wife that if she needed to go somewhere that it would be okay just turn off the AC first.

Fast forward to today. You guessed it, it happened again. This time she said that when she started the car the air was on and all was okay. As the car heated up the noise returned and she turned off the air (not sure about this). We ended up having to get the car towed home and it is sitting in the driveway awaiting my attention.

Has anyone else had a similar experience? Any ideas as to what this might be? Any ideas/comments are welcomed, even if you want to bash me first.

[bastereo]

Take the belts off and spin the pulleys by hand, feel for rough bearings.
On the ac compressor don't forget to turn both the outer pulley and the inner part, the clutch, that will turn the compressor itself.

[HPIA4v2]

Wonder if you are on your original water-pump? If yes, I'll zone in on that one. I have not heard PS/AC/alternator goes bad before WP does on an M64 V8.

[X5isHers]

I plan to get into it today....I will post my findings. Thanks for the comments!

[X5isHers]

After crawling around a bit under the hood today I had narrowed it down to the tensioner pulley set under the water pump by the alternator. I removed the fan and clutch, radiator and all the other things that were in the way. While I was in there I went ahead and replaced the two belts. After I removed all the belts I went for the pulleys. They sounded fine. So I started to test all the other pieces; the compressor, water pump and alternator. Come to find out when I turned the alternator pulley it was very rough and growled a bit. This ended up to be the culprit. The alternator was hanging up causing the belt to slow in turn causing the steering problems and the loud noise dragging on the belt.

Did you know the alternator on the M62 is water cooled? Pretty cool, no pun intended.