Motronic 1.3 for BMW m20b25 : xdf for ***380 HW ECU

[thomas9588]

Hello,

I just turned my BMW m20b25 engine into a m20b27 with some goodies like 240cc Bosch injectors (from SAAB 2.3 turbo).
Running with motronic 1.3 on ***380 ECU HW and 1267356204 soft reference + wide range lambda sensor (LSU4.9).

I am currently running-in the engine, and with the OEM maps, the cold idle is way too rich (~1.4) and really unstable, engine stalls all the time. I succeed in having it stable by reducing the fuel pressure (and so the richness), but then the partial load part is lean. So changeing the fuel presure is not a solution (even temporary).

SO

I just wanted to change the idle fuel MAP for the run-in phase. I did it offline with Tuner pro, using BMW173Chip.xdf and stock173.bin from TunerPro database.
As the richness is 1.15 @warm idle, I divided the MAP by 1.15.
I 've flashed the .bin in a blank EPROM (27C256), then put it in the ECU.

Start the engine, cold idle is still running 1.4 richness, while the low load part is now lean (while it was slightly rich before modification of the .bin).
High load parts seems still as it was before.

Conclusion : I've changed the idle MAP but this is low load part that is impacted...
I have some doubts about the 173 xdf or/and bin consistency with my 380 ECU, does anyone have any information about this?

Thanks

[thomas9588]

please see images