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      09-08-2008, 02:49 AM   #40
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Drives: 2013 E93 M3, Jerez Black
Join Date: Jun 2007
Location: Bay Area, CA

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Originally Posted by boostm3 View Post
Where did you hear this? Has OBDII changed That Much? Used to be, back when the OBDII spec was first introduced on 1996+ models, that adaption was learned while driving in Closed Loop mode only... With the WOT pulls to 6500 rpms that you are describing, used to be that the OBDII BMWs would switch into OPEN loop mode where the engine ran off hard wired maps to which the adaption factors, learned only during closed loop running, would be applied. It used to take something over 40 miles of easy closed loop driving for the engine to adapt to new hardware affecting fuel trims and ignition advance.

Can you direct me to where its written that current OBDII spec is applied so differently? Almost sounds so different, maybe it should be called OBDIII?

!! Paul E! I remember you from long long ago, I used to have a 97 M3/4 with a dinan supercharger.

Anyway, OBD-II only defines the data communications, adaptation is still a function of the ECU/DME/whatever you want to call it, and has nothing to do with OBD-II. Adaptation varies between manufacturers and ecu revisions, and has nothing to the communications protocol.