Possible Causes
WARNING: This page does not describe the selected car, but rather 16 other vehicles, including the 2002 Mercedes-Benz SL500, 2002 Mercedes-Benz S500, 2002 Mercedes-Benz S430, 2002 Mercedes-Benz E55, and 2002 Mercedes-Benz E430. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
Manufacturer does not provide testing procedures for this fault.
Possible causes are air ingress (leak), fuel injector failure, pressure regulator failure or mechanical wear of engine. Inspect and repair as necessary.