Slow Passenger Window

Hi All. I am a newbee to this forum and did search for posts related to my question but didn't find any. So if there is one, forgive me for starting this one.
Does anyon have detailed info on how to adjust the passenger side window on a 2002 325i. My window goes at normal speed for about half of the upward travel and then slows to a crawl for about 4 inches. It does make it all the way up, but I am concerned that it is not going to last long. I have only had the car for 3 months. I did remove the door panel and looked for any binding but was to afraid to go too deep in the door without some sort of instruction. I am a great DIY'r.

Any help would be appreciated!!

Your window motors going. I belive its around 50-100$ at a dealer.

^^I'll second that. The window opening is more curved near the top, so it makes sense that a weak motor will have a hard time. It's $102 at pelicanparts.com, just for reference . . don't know what the dealer will charge. But it's a fairly easy install for the DIY'er.