1984 300 CD
I added a Mercedes Source electric fuel pump, no other fuel system mods. After inital installation the pump would audibly cycle slowly at idle, and pump speed would aduibly increase with engine speed.
suddenly, the pump now runs at high speed constantly, idle or at highway cruise, no detectable difference. Is this a problem or normal?
Also, any ideas of a material to use to isolate the pump from the chassis to lower the audible pumping sounds?