KE Jetronic Help Please asap

[mmark]

I need some experience with this problem, 1988 300 ce, When I force the first gear start the car doesn't accelerate till 2500 rpm then it goes with gusto, If I let the car start in second gear from a dead stop, it is lifeless till 2500 rpm then takes off again.
If I push the gas slowly down from a dead stop it slowly accelerates till the pedal hits the 3/4 mark then the car takes off with the same gusto as a down shift from second to first, even though it's in second gear start, If I force the first gear start from dead stop, again the car feels week till I hit the 3/4 mark with the gas pedal then it takes off again, The last part is the gas pedal is way more linear when the car is cold, there is no snap in acceleration @ the 3/4 mark. If I tap the gas from a dead stop the car will leap forward when cold. This problem with dead gas pedal only occurs when the car is @ operating temperature. I was thinking this could be the airflow sensor (potentiometer) seems like it ???? The car idles great and doesn't misfire, Thanks in advance for any advice you can offer.

Other notable things, I live in central Alberta Canada and winter is on the way. In cold weather the idle is still 550rpm when you start the car cold -2C for now, -30 on the way!. If you don't hold the gas floored it won't start. It does idle nice with no misses. Also the vacum seems low, 3/4 to the left in park when warm & 1/2 when in drive stopped? stays @ 1/2-3/4when cruise is on @ 110kph 65mph whith flat roads, is this about right?

If anyone can provide links to Benz KE Jetronic system and how it works I'd be very greatful, I have a Haynes manual. This is a M103 engine rebuilt with 20,000 km and 4sp auto, I get about 425km to a tank of gas 80% highway@ 110/120kph. I love this car and it is my new hotrod, lol. I have had 11 mustangs over five years, went 4 years with no toys and the wife let me get this car cause I begged! Know what I mean? I have done Plugs wires cap rotor both fuel pumps fuel filter thats it, oh and rims and tires.......

Thanks for any help!!

Mark