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Old 10-11-2012, 11:15 AM
cwinter's Avatar
cwinter cwinter is offline
Here comes trouble!
Location: Dallas, TX
Join Date: Feb 2009
Posts: 8,356
Mein Auto: 2009 328i E90 :)
Originally Posted by Nordic_Kat View Post
I do have a question about alternators. When the SA was giving me the lecture about driving it more, he said something to the effect that "if you don't get the car up to 60-70 miles for a sustained amount of time the alternator won't spin fast enough or long enough to charge the battery." Does speed really make the alternator spin faster? Or is it just plain old time with the engine running that counts. If it's just time, then I could easily double my commute time by sitting in the gridlocked traffic on the freeway.
Maybe you should drive it on the weekends rather than washing it.

(I'm just jealous!)

And yes, what DSX said. Alternator output is varied as loading conditions change BUT the output of the alternator has little to do with vehicle speed (MPH) and more to do with engine speed (RPMs). SAs never cease to amaze me...
2009 328i Sedan - Ordered: 2/24/09 .:. Delivered: 5/6/09
Jet Black | Black Dakota | Aluminum | Premium | Sport | Xenon | CA | Split Fold Seats

Originally Posted by furby076 View Post
You will rue this day, RUE THIS DAY

Last edited by cwinter; 10-11-2012 at 11:17 AM.
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