Trying to do some research on areas of the W211 E55 that may be prone to shorting, improper grounding, electrical issues, etc or anything of that sort.

To my knowledge no wiring changes were made to my car, however my shop is telling me that the wires aren't the exact same as original MB.
Something about the current electrical system on the car is not allowing the vehicle to start, and is damaging ECU severely. I seem to be the only one experiencing something this badly with their E55, as I haven't found any information or help yielding any results so far. As to those that have had their fuel system replaced, could something within the fuel sending assembly cause an electrical issue to warrant the vehicle not to start? Suggestions welcome please, thank you.

(Random Question): What exactly is going on when shifting (+,-) is used and the car indicates gear "5"?? I thought only gears 1-4 were controllable by the driver

 

Could be the relay for the fuel pump or a shortage on a wire somewhere. Good luck

 

first off, is the alternator an oem alternator? wires "not the same" going to what?? is there an aftermarket radio/head unit in car? your transmission is a 5 speed tranny.

 

It is really easy to check the fuel pump and sending unit just press in the two clips on the back seat they are located on the lower part of the seat where peoples calves would be if they are sitting. Once you have the back seat out undo the bolts holding the two plates in place under the seat and see if you have any fried wires.

 

Does your shop have STAR? This is much too vague. You need to have it diagnosed with STAR. It will tell you what is wrong with the electrics.

 

No STAR or any other diagnostic tool works. The damaged ECU would simply not respond to any commands made by any diagnostics, and I've fried a secondary one once it was installed in the car.

The fuel assembly was replaced and the pump properly gets voltage, and all has been checked back there.

green1212 - I had just thought that when in sport mode the driver could only shift 1-4 before it goes back into normal D drive mode