What you talking about is actually an injector cleaner, there are many, many
sold. I’m a fan of Chevron’s Techron as I’ve seen it
work well.
So to answer your question I’m sure some do, there are all kinds of
fuel additives
sold.
However I believe your better served by pulling your injectors and having them tested and cleaned. Magic chemicals in the
fuel can do very little in actuality, to really clean
varnish off takes physical cleaning.
I’ve worked on many of Mercedes Diesels myself from the 220 to the 300D non turbo and the 300TD turbo, I owned them. We even had a 300 CD for awhile which was sort of a joke really, a two door “sporty” Diesel
If you use injector cleaner, it’s best to use it in the tank before
oil changes as it can wash some
varnish and carbon into the
oil.
Those that
work anyway, most I believe are snake oil.