OK heres the deal.. my car looses power at moderate to heavy accelleration... getting on the highway etc... Well, let me kind of rephrase that the rpms fall about 1k, and the car then shifts down.. but then it jumps back up again in rpm..and the car then shifts right back up.. Could this be a problem with the vanos or am i just completely off. I kind of have a slight understanding of how it works.. Im a honda guy so i know all about variable valve timing.. i digress.. Its a 98 528... so ive established that its single vanos. :dunno: Ive been to the stealer.. they checked for updates for my tranny cause they seem to think that may be why the tranny shifts all over the place.. and there are none. I have no check engine light... so im just at a loss. I was funny too cause the SA was like NEVER CHANGE THE TRANNY FLUID! BMW has a lifetime fluid yada yada.. BS whatever.. So any help is always appreciated. Thanks guys..