When the MAF/O2 sensor were replaced, did the tech reset/recalibrate the fuel adaptation?

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Chris
2007 E550 4Matic - 61,000 Km - Iridium Silver, black leather, Sport package, Premium 2 package
2007 GL450 4Matic - 62,000 Km - Obsidian Black Metallic, black leather, all options
1998 E430 - sold
1989 300E - 333,000 Km - sold
1977 280E - sold
1971 250 - retired

"And a frign hat. They gave me a hat at the annual benefits meeting. I said. how does this benefit me. I dont have anything from the company.. So they gave me a hat." - TheDon

Not that I know of.

How is this done, anyway?

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It is a truism that almost any sect, cult, or religion will legislate its creed into law if it acquires the political power to do so. Robert A. Heinlein


09 Jetta TDI
1985 300D

I would like to know also. Anyone?

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1993 400E, 256,000 miles (totaled)
1994 E420, 200,000+ miles
1995 E420, 201,000 miles

You can reset adaptation back to Mean Base Line by re-setting/re-activating the ECU memory . After you have cleared all existing codes [Single flash verification ], you then hold button for 6-8 secs. after the single flash. [wait 2 secs after single flash].. Turn off key for 2 secs, On for 10 and then start.
This is NOT a code clear, it is ECU memory reset. That gets your ECU back to Normal . From there the unit will adapt to the new parts and sensors, but rather then coming back from high adaptation extremes, it will come up/down, +/- as required from a Normal Base value.
The ECU can/will readapt from the old memory by itself with drive cycles [ relearn process] , but if the trims were way out , you can still get codes coming back while the process takes place..so, it is easier to just clear/reset the memory after you have changed parts and have cleared the diagnostic codes ..you are then assured of starting with an ECU that has a Mean Base Line setting value..[ ie..a Normal setting]..which should be closer to proper adaptations with the new remedy parts.
Just a short-cut........

Also, as SB mentions..FP regulator leaking diapragm will supply the engine with unmetered raw gas..not only will the engine suck raw, un-metered gas into the intake from engine vac , but the Fuel Pressure will go higher than spec and compound that problem...that would be a first check..
the same can be a vac leak..a vac leak of unmetered air is read by 02 as a lean condition , so th ECU tries to enrichen this false reading, resulting in wrong A/F mix..
Both reg and vac leaks will force trim levels +/- that it may not be able to handle [ beyond limit].........and result in crap MPG/Running condition.
If one does find a leaking/bad FP reg, it is also a good idea to change the oil.

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A Dalton