DBW Idle tuning

Hi all,
I’m messing around a Mini R53 with a slightly modded engine (Cams, compression, IC and exhaust) and installed a EMU Black PNP; after messing with some wrong settings I managed to start it and got a decent tune to break-in the engine.

The Engine builder decided that the engine needed a bigger throttle, so installed a BMW E90 DBW valve (code is 408238425005). I didn’t find any calibration for this valve, so proceeded with the automatic calibration (that did a farly good job!).

Now for the issue: when I depress the throttle engine accelerates, but once I release the pedal rev drop slowly (likewise the throttle plate don’t close completely), then drops under idle (about 200rpm under), then bumps up to idle.

Looking at logs it closes the plate exactly as the last idle position, but rpms drop under by a far amount.
All this while AFR is reasonably stable.
Somebody got in a similar issue (and how resolved)?
Is there a “speed control” on the DBW system?
Is there any guide explaining the way to tune all the DBW settings?

Thanks in advance for your time!

Hi. Send me the log and file. I’ll take a look at what’s wrong.

Hi, here is the log and calibration:
R53_DBWIssues.zip (1.1 MB)

Thanks in advance