Talal Al Hadidi

Pls. I need to understand how to build high fuel pressure in fuel rails in engine OM642 while there is an open pipe to the return line to the tank ??

Maj. Dundee

Scan for codes in fuel rail for Y74 and Y94.

Talal Al Hadidi

Thanks for your kind reply
I'm asked this because I removed the left fuel rail and see that the valve inside the rail not long enough to reach the return line I point with red in the attached photo


??
so this valve does not control the return of fuel to the tank 🤔

Maj. Dundee

Well then the part was probably installed by a [previous owner. You must buy you parts at a M/B dealer.

Talal Al Hadidi

Dear Sir
I think you mean that the parts is not properly installed by the previous owner ? , I compare it with another car like mine ( ML350 2010 , VIN
4JGBB2FB6AA593877 ) it's the same installation and same part no. !
am sorry to take your time but my problem still the same code P0087 fuel rail low pressure .

Thanks