Still sounds like you have air leaks in the fuel system. When the o-rings failed on my '98 there were lots of bubbles visible in the clear lines, the car was hard to start, and it would hesitate and stumble badly when driving. Never actually stalled on the road, but sure felt like it wanted to.

It's probably best to replace all the fuel lines. Our professional techs on the board have noticed the plastic ends crack, rendering it impossible to get a good seal even with o-ring replacement. My 1998 E300 required this repair in late 2001.

Look for a recent thread from Rick Miley about his '99 diesel. It even includes the part numbers for the lines. I believe there are five or six separate lines.

The techs replace more than a few of the shut-off valves due to fuel leaks as well.

Once a diesel is running, about the only thing that will stop it is lack of fuel. Of course, on this car the injection pump is under electronic control, so there's some chance it could be electrical. Is the cutting out more of a stumble, or is it sudden and total? I wonder if there's a problem with the shutoff valve, or the electrical signal to the shutoff valve?

- JimY