Well, it came to a point where I HAD to go to the dealer as I just had NO time to do anything to my car. The dealer said that the tensioner is getting close to the end, but that's not what was making that loud noise. It was the AC compressor. Aw Fuck. Great......
Since they were there at it, they changed the tensioner too (to the upgraded hydraulic one). Now, if anyone in the future cares to know, a re-manufactured AC compressor installed will run you $1300 and an installed tensioner will run you another $500-600. In the end, after tax and shit, I dished out $2072. What a fucking money pit I'm in with my first year E46. Fuck.
BMW should be paying me for thier guinie pig experiments.