A stiff accelerator pedal could be normal. The W140's are heavy cars, and MB's tend to require you to push harder on the pedal anyways.

A squealing PS pump when the steering wheel is turned all the way to either side could be normal also, as the pump releases excess pressure (I think there was a recent post on this same subject)

White smoke out of the exhaust could be steam if it's cold outside, but in 60F weather it could also be coolant leaking into the combustion chambers though a bad head gasket.

Wheel vibration could be collapsed motor mounts.

190kmi is a lot of miles, and unless you can do head gaskets yourself, could get very expensive very quickly, most people think that the post-facelift (1997-99) cars are better . How much is the car being sold for?

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Steven Harrison

1993 300E2.8 - 196K
2001 E320 4MATIC - 86K