I am very happy with the W124 300E I purchased 4 weeks ago. However it seems to have an issue that has stumped me. When I bought it, it had been standing for some months. On my first drive I stopped after a mile or so and put some petrol in it (46 litres worth) as the tank was empty (does anyone sell a car with fuel in it now?). Pulling away from the pump it was very hesitant, and felt like it "fluffing" under load. I thought it could just be the damp,seeing as the car had been unusedfor so long and had been stood all that time in the open. After 75 miles or so it was less noticeable, and got better and better and was then running perfectly. I took it out today (it had been parked up for a few days) and it was fine, no hesitancy at all from cold, and it was cold! I had to refuel it so put another 46 litres in. Immediately from pulling away from the pump the same hesitancy was there again. It don't think it can be water in the tank, as there would be fuel in the fuel line and injectors would take a few hundred metres to show up. It happened immediately. I am trying to think what it could be - the only thing I can think of is it is linked to having a full fuel tank. Any ideas as I am stumped?