DME Settings for Smog

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M6smitten
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Joined: Tue Jan 12, 2010 5:08 am
Location: Denver, CO

DME Settings for Smog

Post by M6smitten »

I did a search and came upon this post. Does anyone have suggestions on the best DME setting to pass emissions test? Do you all concur with setting #5? Pics of the setting markers might help too.
GWL wrote:
sskang wrote:GWL

Thanks again for your posting.

If the 055 motronic does not have 02 sensor readings.
I guess the fuel economy of a Euro M635 is not as good as the KAT models (though that doesn't bother me much).

I was recently told that the 079 has a "switch" that could be used to change the setting to make it compatible to 055 but are you aware of this?
No I am not. Since I do not use the O2 sensor on my S38 I have been thinking about trying the 055 if I ever find one. If it works I can always use my Miller chip and No O2 sensor. The only reason I would get one is to have a spare. So which ever I run into first is what I will try. There is an adjustment that varies the fuel maps and timing, but I have never used it to adjust my DME because my Miller chip and the Conforti chip before that worked well enough for me.

Here is the information I have on these adjustments. Please note that there is a little difference in what each setting does.

"In playing with my euro M to get it to pass smog, I learned a couple of things. The ECU has eight settings on a little dial inside the box, this I knew. The #O setting is no adjustments, setting 1-7 change the fuel ratio and the timing. You can increase fuel or decrease it, and/or you can retard timing, and/or a combo of both. I used setting #5 for smog, richening the mixture and retarding the timing. I am now on setting #1 that increases fuel richness by 3.9%. The car, with octane boost, runs very very well now. I have no cat. It runs better with this extra bit. The #2 setting increases fuel 10% and that is too large unless you are tuning for that based on engine mods. It is easy to remove the brain, 4 X 10mm bolts, and it is easy to remove the metal cover by unbending the securing tabs. Although, there is a spy hole, so you do not have to actually remove the cover, but you can't see in, and it helps to be able to see the little digits for the setting. As well, I recommend you remove your AFM cover and mark where the cogwheel is set, so you have a reference. Use a dot of paint or something. Setting #1 works for me.

The M Power newsletter specifies a little different for the ECU adjustment positions. They list that 0 is factory default, while positions 1, 2 and 3 are: 3% rich, 3% lean and 6% rich and no timing changes, while positions 4, 5 and 6 are: neutral fuel, 3% rich and 3% lean, all with 2.76 degree retarded timing
."
2011 1 Series M
1974 2002 Turbo
1987 M6 (2/87) - Sold
1984 M635CSi (10/84) - Sold
2012 335 xi
2009 328 xi

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