Bimmerfest - BMW Forums - View Single Post - "Tip-In" and "Initial Acceleration" problems fixed
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Old 07-06-2011, 03:11 PM
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Location: Colorado
Join Date: Feb 2011
Posts: 824
Mein Auto: 2012 535i xDrive
Originally Posted by solstice View Post
I'm starting to wonder if this is mainly a forced turbo lag. A turbo engine is pretty gutless and fuel efficient when the turbos are not used and fast and thirsty when they are. Can it be that the engine is mapped to wait for a deep pedal movement prior to engage the turbos while in D mode? It would explain the weak response and sudden burst of power. When in S mode the turbos are engaged from get go causing a quicker smoother response but also poor fuel economy. It's not really noticeable on the 550 since even a turbo tuned 4.4l V8 has enough grunt without the turbos to get going.
Trust me on this: I've been deep into the pedal and the lag did not improve. I'm not convinced that it's turbo related - especially with the twin scroll design that comes on early.
2012 535ix Space Gray, Cinnamon, SAT, Premium, Prem sound, Cold W., Sunshades, Gloss Black Grille, Gloss Black Side Markers, RE970AS 245/45/19 non-run flats that run very smooth + quiet and also correct the otherwise optimistic speedo
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