nothing really they have all but been elimanated from the fuel systems, early 325e's use to be covered in them, seen 5 and 6 dampers scattred through the system and a couple years later in production they are all gone, it's like a mini regulator that is supposed to smooth the feed from the pump, but that's what the main pressure regulator does, seen a few of the old inline units screw up and block flow killing the car, but most of the time they have self destructed and rattle, haven't seen one of those pump mounted ones crap yet, maybe they suck less

Quote Originally Posted by Milkboot
Ooooooh, Does this this lil damper do?