[EHoth11]

I recently acquired a stage one tune for my 2013 f30 335i(pwg) I went bm3 and used the trans tune as advised.

I flashed and ran into an issue today that seems to be trans-related, but I'm not entirely sure. under moderate acceleration, the car makes a loudish lugging noise leading me to believe something is slipping. no codes were thrown or warnings. It sounds and feels like the noise is coming from behind me. Flashed back to stock and all is well, the car shifts between gears completely fine only under acceleration with the tune did this occur. currently at 100k and have not done the trans service yet, I hope that maybe a fluid change will resolve this issue but I can't say I'm confident.

if the problem persists beyond the fluid change do I even bother having it fixed or maybe try to buy a used transmission if the issue is related? Or simply cut my losses with the tune and keep it stock?

side note if anyone knows any solid BMW mechanics in the north Atlanta area that won't kill me on price please let me know, or If anyone who does their own work is willing to take a look/help out id greatly appreciate it. I'm a college kid and unfortunately don't have unlimited funds.

Any thoughts and ideas would be much appreciated.

[LA1Z24]

If the trans was slipping, the DME would kill boost and power till you switched to the next gear.

[n55david]

Uninstall the trans tune and see if it goes away?

[EHoth11]

The issue still occurred after the trans-tune was removed, but I still had the dme flashed.

[n55david]

Originally Posted by EHoth11

The issue still occurred after the trans-tune was removed, but I still had the dme flashed.

Post a log on the car at wot,, from atleast 2500 to 6500rpm. Multiple gears if possible, 3rd, 4th etc.

[DrBall]

have any video by chance that captures the sound? and like N55david said.. logs would certainly help the pros on this forum hone in on the potential issue..