Motronic 2.1 Orange or Blue?

[Freelancer]

Hi,

I got a question. Am replacing my Motronic with a spare that I have. The one in my '91 has an orange label and the spare has a blue label. The numbers all match.

So, is there any difference between the modules other than the colour of the label?

Also, while I had them apart, I found that the one in my bike had a luftmeister chip. Any word on whether or not these were any good?

Thanks,
Freelancer

[Laitch]

I think the orange label might go better with fish.

[Freelancer]

I've reviewed the parts-fiche and there are 2 ecu's available for the '91-'92 4valves. One seems it may have been for a catalytic converter equipped model. The 2 units have different part numbers though. :dunno2:

Also, the part #'s on the fiche are different from the numbers on the labels.

Anyway, went ahead and swapped the guts from the spare with the one on the bike (spare had a busted mounting tab).
The Bike started up and after a few seconds settling in it runs pretty good. There are still a few quirks and will have to see if it fixes the intermittent coil problem I've been dealing with in the other thread.

Still am interested in knowing what are the differences between these. Maybe one was european model or something.

Later,
Freelancer

[Laitch]

Part numbers seem to govern BMW's supply scheme—where numbers are superseded by different numbers and those numbers are superseded by others. Adding color to the systme for anything critical seems uncharacteristic except for paint, of course. The label colors and numbers (when differing from microfiche) may mean country of origin or contract- versus factory-made. Reading bimmer forums, I found owners wanting motronic ECUs with differing label colors but in the end the ones I read simply went with the part number.

Your action makes sense, Freelander; good luck with it.

I wonder if Marshall can shed some light on the label color preoccupation; he seems to have had plenty of bimmer experience.

[The Mighty Gryphon]

I think that the 4 valve bikes could come with or without a Lambda sensor to sense residual O2 in the exhaust and use the data to adjust the fuel air mix. 

Not sure, but the labels may indicate whether it was for the lambda sensor or not.  In the absence of the sensor there is a manual mixture adjustment that is set with an exhaust gas analyzer. 

I'm sure someone with more knowledge will set me straight on this.

[Inge K.]

Cat models did have a green label, non cat models did have a blue label up to 31/12-91
and a orange label later.....the Bosch part number is also different on cat vs. non cat.

[johnny]

greetings...

i pay attention to laitch... life is too short for incorrect pairings...

green label  - foul...
blue label  -  cloven hoofed beast...
orange label  -  fish...

j o

[Freelancer]

Inge K's answer is what I was looking for  :2thumbup: ...,though getting getting one of laitch's and johnny's non-sequiturs also made me smile.(Fish, I agree with....but which type? Smoked Salmon? Buttered Trout? or Jerked Tilapia?) :)

So yeah, I think latch was also correct. That in addition to different model year, the label colour change also reflected a different supplier/country of origin. (On one the case is stamped made with the word MOTRONIC while the other doesn't. Also one had a chip/circuit labelled made in the Phillipines where the other was not.

Anyway, just want to say thanks to everyone for the input and answers.

Later,
Freelancer