Ramodeys

My E55 starts and runs for various times ranging from 5 seconds to 30 seconds then sputters out and dies. I have changed the crank position sensor, fuel pump relays, full fuel system (MB warranty-fuel pump, sending unit, tank). The fuel pump has pressure and is getting voltage. I have looked over other common issues online and it seems to differ from them. I had a tune on the car from a reputable source which I thought might be the problem but I put the tune back to stock and still have this issue. Mod wise I have headers and smaller supercharger pulley. I am not sure what else could be causing this issue, it seems to be electric. The car runs fine and I can rev it perfectly but it ends up sputtering and dying no matter what I do. The battery and alternator were replaced so it doesn't seem to be a power issue. It seems as if the ecu is telling the car to cut fuel.

Plutoe

Did you do a DAS Xentry quick test prior to using your FUYAA

Ramodeys

Thank you for the response, I just got it fixed. Turns out they didn't use the proper wiring harness adapter for the fuel pump. They had a neutral going to a power wire so it wasn't getting the proper power. I switched the pins and it runs perfect now. BTW what is Fuyaa?

coupesedan

you sure both pumps are running?

my car would start and run and do everything fine with one pump running in reverse (new pumps no adapter harness)

Ramodeys

I hope both pumps are running, feels like they are, pulls strong right now. Before it would only prime and I swapped 2 of the pins out of the 4 so it might just be one pump running twice as hard. I’ll pull the lid and check it while running.

SICAMG

Glad you got it running but how did you get the fuel warranty done at the dealer and end up with the car ? How did you get it home ?? LOL
Glad it ok now!

Ramodeys

I had it towed out because they were trying to charge me 500 just to diagnose the issue which they were at fault for. Tbh they caused so many problems to the car I just wanted it out of there. They kept ordering the wrong parts, destroyed my oil cooler, messed up my heat exhanger, and just did a poor job in general.