With the diesel, I believe you always hold the accelerator down just a tad to start. My 1981 300SD starts in about half a second so the start and the push on the accelerator is almost simultaneous. When the valves needed adjusting, it started the same but would die unless I gave it a medium amount of throttle until the engine got warm; after adjusting the valves, that necessity went away. I have about 269K on it now.