bahrendt

I had an 2005 E55 that I recently sold that was having issues stalling on hot days at freeway speeds after driving aggressively. Fealt like it was starving for fuel then would die, after about 10 mins of sitting it would restart and drive hundreds of miles just fine. I thought the issue was fixed but the new owner just told me it happened again.

Yes, I know Mercedes Crank sensors are garbage, and yes, I already replaced it. Issue is still there. I know the 203s were having fuel pump issues that were causing symptoms like this, do you think i should throw some fuel pumps at it? Dont know any surefire way to diagnose this since it is so intermittant. When it happened last time, i pulled off the fuel rail cover and it had fuel pressure. Maybe it was vapor-locking though? Anyone else see this? BTW, intercooler pump is shot but i dont see it causing the stalling issue.

BenJ

Perhaps the iat's are getting hot enough to cause shut down?

AKnight55

Intercooler pump.. Common issue

Feels like driving an E320 when its dead.

bahrendt

Doubt that the IATs are getting that high since the supercharger is still functional, then it all of a sudden the engine shuts down. Not just "E320" dies, but "absolute loss of power" dies, engine completely shuts off. I will recommend an intercooler pump anyway. Johnson CM30 seems to be in the cards. I will probably visually inspect the fuel pump to look for anything out of the ordinary.

Vader55

CM30 will be a game changer for you.

cij911

Log the car 100% of the time...get data to show you what is happening...Car shutting down completely does not sound like an IAT /pump issue to me....If it is intermittent it sounds more like a crank sensor (which I know you said was replaced)...Also check the cam sensors...(Sounds more electrical than fuel as fuel would generally causing sputtering, misfires, roughness, etc...) Good luck

bahrendt

cant log the car since it isnt mine any more. I have seen the cam sensor trigger the CEL a few times on some other 55 kompressor motors that i have worked on but never dying. I guess i will check it to see if it has any stored codes. Might just tell him to visit the dealer since this problem may turn into a wild goose chase on my end.

outrun

Do you know the buyer? I am surprised you are fixing the car after selling it.

ScottW911

I was wondering the same thing.

Ryououki

I would bet it's your fuel pump. When they start going bad and overheat, they limit flow and/or stop sending until they've had enough time to cool down and then start working again.