I have been reading some of these posts and find them very helpful, I just hope you have an as good solution for my dilemma.
Any assistance will be greatly appreciated.

I've been having this problem with my 740 2.3 Turbo, (137,000 miles).

Whenever I first start the car, even if I have driven it a few minutes prior; it has absolutely no power under load, especially going uphill.
The turbo gage goes way up high when I floor the gas pedal, but the car hardly moves; feels like it's starving for fuel or choking.
My mechanic has not been able to find a solution, he claims all the codes read normally.

When it first started doing this, what I would do is pull to the side of the road and shut the engine off, re-start it after a few seconds and it would drive like a champ, with power to spare until I got to my destination.
Then I would have to do the same procedure over again every time.

Lately, it has gotten worse,...... it will take some times up to four times (shutting it off and restarting it immediately after) for it to finally work normally.

What I have noticed also is that when it does this it leaks oil out of the right hand lower side of the motor onto the exhaust pipe, (have not been able to pinpoint where from exactly, since it is an oily mess underneath). When I park after a drive, smoke comes out from the under side, from the oil dripping on the exhaust pipe.

Don't know if this has any relationship to the above; in the lapse of 2 months apart, when I came to a traffic light and waited, I noticed very heavy bellowing of white smoke out of the tail pipe, and it slowly minimized and dissapeared as I drove off. It has done this two times in the 2 month period.

Any good suggestions?