Ken,

Welcome to the site. How many miles on your new Benz? When you do this acceleration event, does the car smoke a lot?

It seems you are taking care of the routine things. You should also check the valve lash or gap as these engines are sensitive to this dimension. As the engine runs the valve kind of pounds its way up into the head and the gap closes. This can lead to hard starting and poor power. Also, there is a turbo charger on the car that has an output pressure regulator with a connection to the fuel injection pump. A Diesel needs more fuel to make more power as it always gets a full charge of air (no intentional throttling of the intake volume). So, there is a means to sense intake manifold pressure and let the injection pump know it should add fuel per injection squirt the higher the pressure goes. This system is susceptible to being clogged with the exhaust particulate and other stuff, mostly due to the exhaust gas recirculation system and the blowby gas induction system.

The car should smoke somewhat on hard acceleration, and the engine performance should be noticeably stronger as rpms climb above 1,000 or so. If you get no smoke, the chances are the injection pump is not getting the signal the turbo is putting out extra air. So, you don't get a boost in performance.

Additionally, a bunch of stuff works off vacuum. As noted, Diesels don't make vacuum very well, at least not on purpose, so there is a vacuum pump to create the vacuum. The brakes, transmission, door locks, shut off valve for fuel to shut down the engine, air conditioning system and so on, all depend on the vacuum system. As the car gets old the lines, especially the connectors that are made of rubber, fail. This makes the vacuum system weak. As it fails to provide vacuum all these other functions begin to fail in wierd ways. It is not that hard to figure out and fix though and the parts are not too costly.

So, do a search on "Alda" (the intake manifold pressure compensating feature on the injection pump), or "banjo bolt" (the connector you clean where it comes off the intake manifold), and "Vacuum System" and you will find these things come up all the time and others have donated many hours of their time to teach us what they learned on the subject.

Good luck and enjoy the car. Jim

__________________
Own:
1986 Euro 190E 2.3-16 (291,000 miles),
1998 E300D TurboDiesel, 231,000 miles -purchased with 45,000,
1988 300E 5-speed 252,000 miles,
1983 240D 4-speed, purchased w/136,000, now with 222,000 miles.
2009 ML320CDI Bluetec, 89,000 miles

Owned:
1971 220D (250,000 miles plus, sold to father-in-law),
1975 240D (245,000 miles - died of body rot),
1991 350SD (176,560 miles, weakest Benz I have owned),
1999 C230 Sport (45,400 miles),
1982 240D (321,000 miles, put to sleep)