There are two possible routes to take in maintaining your diesel injection system, the way the Mercedes factory shop manual says to do it, or superstition, pagan rites, folklore, and hearsay. For those of you cannot stand to read the factory shop manual this is a cheap, harmless but futile way to play witch doctor. It is kinda fun to do a few times just because you can and it is a good way to empty old containers with a little oil, etc in them. It is just as effective and cheaper than Diesel Purge or Seafoam, etc. Mazola works too and it smells better when it burns, so it may be more pleasing to the gods of compression ignition.