Hi there,

posting here cuz community of c63 much bigger than ml63, engine is same.

I have rought idle on D when I stopped on red traffic light, engine and transmission trannys was changed and thats not helped. No errors on that thing.

Found errors only on full tank
3699 Fuel pressure control: The upper limit value is reached P0191 // come first time right after refuel till full tank
3699 Rail pressure sensor has malfunction // second time

anybody knows what a hell is going on?
No check engine, checked vacuum leak, didn't found anything.
Checked by star diagnosis fuel pumps, both give normal voltage.
I saw lot of threads about P0191 and seems there is no solutions, or maybe I didn't found any?

Did you find a solution? I’m having a similar problem with my 2009 ml63.

thanks!

Hi,

errors due fuel pump which was replaced

Rough idle was fixed by replacing chain tensioner.

I'm having the same code. I also replaced my fuel injectors, fuel pump and spark plugs. I get random very rough idle that often leads to the car stalling multiple times before running fine again.

you both should ask for smoke generator on car repair stations to check if engine have vacuum leaks