Good evening everyone!
I have been somewhat active on e90 post in the past in regards to our 335i and my late x6. After a 4 month stint in C63 AMG, I'm happy to be back in a BMW - a 2010 750Li xdrive to be exact. The m-sport package is what sold me on this particular car at my local dealer, and I decided to take quite a financial hit and trade in my c63 after only a few months. More on the car later as I've noticed a few things which concern me about the car so far.
Let me begin by saying that the dealer claims there is nothing wrong with the car (big surprise there, in the fact the reason I sold my X6 back in November was that I couldn't put up with untreated problems anymore) but I'm not giving up easily this time.
My first concern is a noise, a "whine" to be more exact, which is very annoying at low RPMs when taking off at a light or driving at residential speeds. This noise can be heard from inside and outside the cabin. I've done my research on this forum and according to the dealer, it is NOT the oil pump others have had problems with - right. I uploaded a short video to Youtube which captures this noise fairly well, especially in the second half. While the title screen reads "cold start", it is infact a "cool" start - no cold revving here!
After finally getting an external microphone for my gopro and recording a fantastic video of the engine / turbo sound in the 335i, I was excited to try it on the N63 engine. I was shocked, yet amused by the resulting noises. At full throttle all is well, but please feel free to take a listen to it at lower speeds, video below.
Lastly (and no video of this unfortunately), the car vibrates quite a bit (felt in the steering wheel and butt region) when accelerating moderately but at low rpms in the 1400-2000 range. It feels like once boost builds up (without downshifting) it starts to vibrate and that disappears instantly when the foot is lifted off the gas. Likewise the vibration is also gone once RPMs go above 2000. This works very well in every gear at the according low speed (other than first of course), and dealer claims it's normal. Is does not appear to be a tire / wheel or road vibration as it only occurs when accelerating. No e90, e92, e70 or F10 loaner, our 335 or the previous x6 or any car I've driven every did this.
The tech at the local dealer actually said this in reponse to my conerns "well what do you expect, it's an upside down V8!"
In any case, I would appreciate any input you may have and I will try to add the car to the garage and post some pictures!
Regards,
Doenermann