Originally Posted by Zulfiqar

Yes your car has a fuel pressure regulator, its built into the fuel filter. (your car will have a 4 hose filter rather than 2 hose)

When you replace it make sure that its either a genuine mercedes or Bosch filter. The others have a bad tendency to either squeal or act stupid.

The filter is bolted to the floor of the car like the W124 and requires clic lock pliers to undo - if you dont have those pliers you can tear off the clamps and use screw type fuel injection hose clamps as replacement.