[BradleyHolmes]

I'm using a Speeduino v0.4.3c board with a BMW M50B25 engine and a Bosch Motronic 3.1 ECU. I tried to start the engine, it runs very rough and stalls after a few seconds. I have checked the fuel pressure and the spark plugs and they are fine. I have also checked the logs and the error codes and I see that the engine is running very rich and the O2 sensor is not working properly. I'm wondering what could be the problem and how to troubleshoot it.

[runesm]

Are you using speeduino and a motronic at the same time????

But basetune is only to get it sputtering, sometimes started. You need to tune it, thats the whole point of a standalone.