I have a 01 ml 430 with 90,000 mi. Was running great till I parked it at work. Got back in after work cranked fine but no start, not even a cough.
Sounded like no fuel and or no spark. Had trouble with the sending unit on the fuel pump not working right soooo thought I would begin there. New fuel pump unit with filter. still would crank but not start. Bled some gas out of the fuel rail seemed like some pressure,enough to spay to the radiator. next crank postioning sensor, after some doing that was changed. now when I try to start it nothing happens. I charged the battery, my security light flashes no messeges on the odomenter display. Checked with a voltage meter on the starter selenoid will someone tried to start it, doesn't seem to be getting power. Between fixes the car stayed in the garage and didin't move. Got any ideas? Ignition switch, securtiy sysytem? I tried taking the battery cable off and on, locking and unlocking with the key fob, and using my other key, same result. Hoping it is something I'm just overlooking.

Is the engine getting any spark? Did you remove a spark plug wire & crank the engine to see if there is any spark?

While the starter is operating can you hear any ticking noise from any of the injectors?

__________________
MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
Mercedes Benz Star Technician (2 times)
44 years foreign automotive repair
27 Years M.B. Shop foreman (dealer)
MB technical information Specialist (15 years)
190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)
Retired Moderator

Long story short, it's running now, replaced the fuel pump, doubt it was the problem but sending unit wasn't working,so an excuss to change it, and the postioning sensor, probable fix, to the dealer who said I was missing some fuses, ??? Took the dealer a couple of days and a new battery to fix, still running. I checked fuses numerous times, could have miss placed one?? thanks.