As is very common, the original door brakes for the 2002 were broken. They still limited the maximum opening of the door but had no mid-point detents or springs. Upon disassembly, I found the broken bits in the bottom of the door. There are a couple online sources for OEM replacements and even some nice upgraded ones but they were too expensive and I love a DIY challenge. I read about people using E30 door brakes but couldn’t find a decent guide. Here ya go:
Step one is finding some decent E30 door brakes. The local pick-a-part yard usually had some E30’s and I was able to find some that weren’t very rusty.
Next you need to modify them to fit the 2002. I have heard that they bolt right in but the ones I got had a bolt spacing slightly off from the stock holes in the door. This was easily remedied with a small round file by elongated/ slotting the holes a bit. Lastly, the E30 door brake is a bit long. I held the 2002 door at the maximum desired opening and measured the distance from the door to the pin bracket on the jam. I believe it was roughly 2.5-2.75 inches. Measure yours to check. I then drilled a hole at this length in the arm and cut off the end. Note that the metal is very hard and was very difficult to drill.
Finally, I bolted it up and made a couple small plastic spacers to center the arm in the bracket. It works great and will hold the door fully or halfway open even on a hill.