I have the same problem, HAD. Every time when the engine was hot I had to turn the engine over for ten seconds or more and it smelled like there was too much gas. I also noticed that if I pushed the pedal all the way down it would start.

The problem was pretty simple.... The metal flap for the air intake was getting stuck. I can't remember the name of it but under the air cleaner where the air goes in, that round metal flap is suposed to have a 0.05" clearance around the preimeter of the openning. Mine was too close to one side and getting stuck. It was an easy adjustment. There is also a level adjustment that is done with a small punch if the flap is too low or high. If too high you just tap a pin on the outside of the housing down a little if it is too low then you have to take it all apart and punch from the other side. The pin is located left of the rich lean adjustment screw.
I then adjusted the rich lean mixture adjustment with a 3mm allen turning left until the engine sputtered and then back to the right until everything was smooth. My 88 260e has never run better. I also noticed the throttle linkage loose and tightened it as well. All is well again yahooo!

Hope your is just as easy.

good luck