I have a 300D with 250k. recently the car wouldn't start or try to fire up at all until you shut the switch and try a second time and it fires right up. this is a recurring problem but it will always fire right up on the second try. The fuel lines have been replaced a few months ago all the way to the tank and there are no fuel leaks anywhere so I figured the lift pump might be loosing its prime and I tried a little experiment. Before starting up in the morning I used the hand primer pump about 10 strokes and she fired right up first try. This method even worked last week when it was only 7 degrees. I pulled the lift pump this week, opened it up, inspected it and exercised the springs for the checks to make them a bit stiffer. Now when I bring up the rpms a bit the fuel flow throgh the primary pump is like a water jet and the power is up noticably even though it was quite good before but she still wont start the first time around after sitting a while. What else could be causing this? Is the fuel draining out of the injecter pump somehow? The car runs up the highway beautifully with all kinds of power.