SMG Compression Spring without dropping transmission

[thetypicalm3guy]

Hey guys,

Got the dreaded SMG light and car only has R, 2nd & 5th.

Replaced the GPS with 2 different used units and still getting the shift gate mid position can not be found.

I remember looking at the detent springs when I did the clutch in 2019 and I can’t remember which one I replaced. Apparently they are different sizes and I ordered the 2 of the same springs.

I decided to blindly get the spring out and to my surprise, it’s now out. Does not appear broken, but is it the skinny long one? Is it possible that it’s worn?

Any other thoughts on what it could be?

You need to run SMG adaptations

[sapote]

I decided to blindly get the spring out and to my surprise, it’s now out. Does not appear broken, but is it the skinny long one? Is it possible that it’s worn?

This is the detent spring for the Gate shift rod; there are 2 more parts to be checked: a pin and a roller which riding on the said shift rod. If the roller broke then it could jam up the shift rod at some gate positions, causing miss gears.

Maybe use a magnet to pull the parts out, but be careful don't let the magnet sucked into the gear train then you have a bigger headache.

[03_m3]

I know very old thread, but wanted to add a data point here. I have SMG and it was having trouble initally with 2-3 shifts, then most all shifts. Would take 3-5 seconds, or find the next higher gear. Eventually just went to neutral and would not go into any gear. There were no strange noises or grinding. Looking in INPA no codes for GPS, only error 48: "gear not insertable" in German.

Without removing the transmisison, I did remove the trans brace, exhaust mid section, front of driveshaft and GPS to be able to hit the spring plug with a screwdriver.
I was able to access the top 3 springs with tiliting the trans down, also the spring #9 on the side behind the screw in plug PN 23311228405 which was also good.

Finally, with encouragement from @Icecream I was able to remove the pressed in plug after an hour or more of hitting it with a angled pry tool and screwdriver. I was happy to see spring #6, PN 23311228397, was broken into 3 pieces! The roller holder was also a bit beat up, not sure exactly how this spring being broken will not allow it to shift, but once I removed it the car would now shift. I was able to replace the roller, spring and plug by pressing it with a small socket and using pry bar against the socket to push the plug in the trans. I guess w/o the spring intact that roller just bounces around and perhaps stops the shift rod from moving?

I have driven a couple hundred miles and it shifts great now. 😀

[WOLFN8TR]

Good info. 👍