If you like, you can skip directly to where you can buy this part.
We sell good, original BMW, used E28 ECU units. The price is $130 plus shipping for the Motronic 1.0 pre-1988 units.
According to one official source catalog, the BMW price for this would be upwards of $1,800 for a unit. Whoa!
A Europe-based vendor is offering new units for 645 Euros. Today, that’s $834. Whoa! The same place sells a not-new unit for 135 Euros. That comes out to $175 or so.
I’ve seen one guaranteed never-used unit be advertised on a BMW forum for $150. That seems to be a good deal. But … the post is 13 years old.
Some of the mass-market sellers such as eBay or Amazon have good prices too … how reliable they are … I don’t know.
It’s probably safe to say that our used units are price-competitive.