1997 E300d Intermttent No-start

[msarti]

NEWBIE NEEDS HELP! I OWN A 1997 MERCEDES E300D AND THE CAR RUNS LIKE A DREAM FOR WEEKS ON END, AND THEN DOES NOT WANT TO START. RECENTLY I HAD MY INJECTION PUMP SERVICED DUE TO LEAKING AT O-RINGS ON TOP OF PUMP. THE FUEL SHOP THEN TESTED THE PUMP AND SAID IT TO BE FINE. ALSO REPLACED GLOW PLUGS AT THE SAME TIME. GLOW PLUG LIGHT CYCLES NORMALLY. I DID NOT NOTICE ANY OF THE RED AND GREEN "FLASHING" LIGHT UNDER MY REAR-VIEW MIRROR. SPIN ON FUEL FILTER IS NEW. THIS PROBLEM OCCURS REGARDLESS OF WEATHER CONDITIONS BUT ONLY SEEMS TO HAPPEN WHEN THE TANK IS BELOW 1/3 FULL. ANY HELP WOULD BE GREATLY APPRECIATED AS THIS IS MY WIFE'S DAILY DRIVER. THANKS IN ADVANCE.