masterdog

Hi everybody,

I have an ECU in my car ('86 BMW m635csi euro) that I believe used to belong on Porsche 911 )).
It is Motronic M 1.0 Motorsport, Bosch p/n 0 261 200 055 (at least it says so on the cover).

Here's what I've learned about my ECU so far:
-My car has Air Slide Valve instead of ICV, so someone has removed the components responsible for ICV from the PCB
-ECU is originally for no-cat models, so nothing was changed there
-I _think_ that it was 4k ECU that was jumped later to work with 8k chip, also one of the caps was removed and jumped and some resistors removed
-My guess it's either 051 or 078 unit from euro Porsche 911
-The custom op-amp that reads flywheel seems to be of the correct part number (dunno what to make out of that)

On the side note - I'm having trouble adjusting the mixture (with O2 sensor installed for the purpose). When tried to convert to Miller MAFS it has gotten so bad, engine was unmanageable (with no vacuum leaks (smoked), fuel/ignition system new/checked etc).

I've highlighted the bits removed by someone in the photos (I've replaced the capacitors myself):







A friend from bimmerforums with the same car has taken his unmolested ECU apart and took some photos for me.
After digging through the specs of some components I can only see few (major?) differences:



Basically I'm trying to figure out what the hell is it in my car and can I still make it work right by replacing some components?
Maybe my injector's pulse wrong (engine has new low-impedance injectors now of correct p/n)?
How do I make sure I have the right transistors/whatever to drive them right? How do I test to make sure?
Maybe my AFM is wrong? (it's of later type with linear output signal), maybe my ECU expects an older one (although map would be in the chip and it seems to be of correct p/n)?
What does yours look like? (I showed you mine, it' only fair to see yours now )))

Any little bit of help is appreciated!

champignon

Perhaps a dumb question, but if you are sure that your car has the wrong ECU in it, could you not search for the right ECU on ebay or other sites that sell used ECUs? Given the age, and likelihood that there were a lot of the correct one made, you might find one for a pretty cheap price, like $100.

masterdog

That's the problem - 055 ECUs are very, very rare.
They are model-specific and were ONLY used on European M5 (e28) and M6 (e24).
I'm looking at around a grand IF I can find one...

masterdog

Come on people!
Anybody?
Am I in the wrong forum??

ECU Doctors

I'm going to have my engineer answer you later today. He'll be able to tell you...