mercerb

Hello, I need some help please. These symptoms have been getting worse in the year I've owned the car. It's at the point where I can't drive it now. I have a 1987 190e 2.6 with 130k. The car will start immediately and run great when it's cold or been sitting a while. However once it's warm it starts to idle inconsistently and will hesitate on acceleration. I found that if I flutter (can't think of a way to describe it) the throttle during acceleration it will almost accelerate normally. When stopped if I hold the throttle to the floor it will almost immediately quit. Also, once warm it will not start unless you are pumping the throttle or holding it to the floor. Any help would be appreciated. Thanks