What ECU to use

[Leonstt]

Hi guys,

I'm thinking of swapping my E30 318i M40 with M52B28 from an E39. What I'm not sure about is the ECU since E30 and E39 are very different. So much less electronics on the E30 chassis.

Now, will this be a problem? Can I use the factory ECU That comes with the M52 engine? Or I have to get a standalone? I'm not looking for a crazy power build just a nice daily driver. So drivability is more important than anything else

Thanks

[Northern]

You can run the ECU from the E39, but EWS and any emissions stuff you aren't running needs to be flashed out.

You can pay someone to do this, or you can DIY it.
DIY option requires you to wire an OBD2 port into the harness or purchase a 20-pin OBD2 adapter (OBD2 port is cheaper, and worth the effort for reading of codes or resetting CEL), an INPA K+DCAN cable, Romraider (Free), and MS41 Quickflash.

DIY flashing/tuning details here:

https://sites.google.com/site/openms41/home

[TobyB]

Is this an M52tub?
Easy way to tell- iron or aluminum block.
The E39 got at least 3 variations on the 6, with 3 different
engine control schemes.

t