I know it's a completely different chassis, but I had a similar problem with my '95 E320. It ended up being an OVP relay. Your car has one as well. Not sure if they are as problematic on your chassis...
Your looks like this...
http://www.***************/secure/PartImages/2015400845.jpg
I think your car has 2 fuel pumps, which almost makes me want to bet that both are not dead at one time... Sounds like an electrical/ relay type thing to me...
-GH