11-30-2012, 08:29 PM
Join Date: Nov 2011
Location: Topeka, KS
My Ride: 2002 M3
| I'm near certain it's the compression springs. The GPS will show a pattern in the way that it skips gears, like go from 2-5 or something like that.
Turn the setting on your shift down to 2, drive normally, shift at low RPM. I bet it shifts just fine. As soon as you put your foot into it, or turn up the setting and shift at higher RPM, it will just flash the next gear until you let off. Once you let off and it selects, then you're fine until you shift again.
If that's what it's doing, it's your compression spring. It's not easy to change, but it's definitely doable.
This is the part number of the spring that was broken on mine: 23311228397. Look here for how it goes together: http://realoem.com/bmw/showparts.do?...56&hg=23&fg=15
Also, as for changing it yourself, look at this DIY: http://www.m3forum.net/m3forum/showthread.php?t=396595
Make note of the observations I posted at the end. The original author added a lot of unnecessary steps, mostly in the engine bay. Really, you just have to loosen the fan shroud, unhook the air box, remove all of the shields and crossmembers down below. Remove exhaust, drop the transmission crossmember and lower it in the rear until you can reach the plug. It won't be easy to remove.
FYI, the spring only costs a few bucks.
2002 BMW M3 - Stock