Are all the 2006 BMW X5's faulty with top end problems at 108K miles. Have white puffs at times when idles too long, then hard to start, but was told that oil cold have been changed to different type synthetic...recommends Castrol on engine at filler cap. Also, I am receiving this battery and voltage problem now and do not know what to do...think the alternator bad, only 108K on the car. Put new battery in and had to tow 60 miles because like many others, in the summer of 2012, the heat gauge was stuck because the X5 did not recognize the new battery...so another $105.00 at dealer for "diagnostic" as they said to program the battery.....been teaching electronics for 25 years, still looking for one of those "programmable 12V Auto Batteries". Worked fine for about 2 months and then all of a sudden, daughter in car with my grand kids and the car fails, trans light on, and ABS and other 4X4 indicators. Jump car, runs well for less than one week, and first cold snap being this weekend, all goes haywire which indicated bad battery. On way to work this morning and have brown out and shut down of electrical system, tow for $75.00 and charge battery at my school and now trying to determine the problem. Is is the alternator or the voltage regulator. This car has gremlins and electronic demons and is beginning to resemble the misery of Range Rover owners. My 1996, 328i is great car as is my 1974 VW Bus....dependable.....if before 1999!!! Maybe prince had a point with song "1999"! Work at a school with brand new $10k scan tool system, getting now waveforms from the Alternator or Voltage Regulator indicating past problem or not on top of it yet............I need help!!!!!!!!!!!!!