Salim's , Gus was recommended to me by a friend as the local MB shop would simply try parts until they finally found the issue (at your expense of course).
When our S420 had the Vacuum issue, I got the same thing. Now it's this and now it's that and in the finial analysis it was never fixed. The 4th time I went to pick up the car Gus said just a minute I need to reset the key codes and opened the trunk, pull some fuses replaced then very quickly shut the truck and it vacuumed shut and said all is fine.
But a week later as usual the vacuum issue was back just as before. Before calling I wanted to review the fuse box Gus messed with. I looked at the fuse info in the trunk and two of the fuses referred to the Vacuum pump. Bells kinda went off so I pulled the two and replaced them AND walla the truck and the doors would vacuum shut again. And the car has been that way ever since. Once a week I pull the fuses and all is fine. Hence the pump needs to be reset for some reason.
Obviously Gus knows this but is at a loss to repair it OR he wants me to continue to bring the car in for more parts and labor. In any event I don't need either one.
I never called Gus and challenged him on his key code fuse trick. But needless to say if he is willing to charge me for a new vacuum pump, driver side locking mechanism and many hours work that was never the issue this is not the place for me.
When it comes to Brakes, Oil, Tires, Cooling etc issues I have taken it to the Sears shop in Southgate they have always done it right the first time and if they can't they won't.