Just drive it and put a can of K-44 in a full tank. Change plugs and oil afterwards, then tune. Done deal. I am a former old-school MB mechanic from that very time.
Please be aware that I have no relationship whatsover with the following product. It is just what we used, based upon non-compensated results. Old-school reality like Marvel Mystery Oil. It is what it is, and needs no endorsements.
Worry more about the pattern than the pressure. Parasitic spray from deposits is your enemy. You need to get rid of them first, K-44 does that. It is literally pure Techron that Chevron is so orgasmic about, but it has been around for about 30 years. Chevron adds it to their fuel, but in minute doses. Much like white truffles to a Subway sandwich. Infitesmal.
It is normally found at better shops for sale, or Firestone dealers. About $17 a can. MB techs love it, those that know of it at least. It is the anti-gummer and varnish remover from hell in all regards.
We do not and never did use crap additives that do not work. Customers pay enough already for the service, they expect tangible, accellerator pedal proven results, and we are expected to deliver. And that we both did and do.