RE: ignition wont shut car off
I experienced a similar problem with my 1995 E300 a few years ago. When I took it to the dealer's they ran some tests and told me the vacuum pump had gone bad. That was replaced, and the problem went away. Other problemsI experienced with the engine not shutting off were hard steering and hard brakes (almost like no power steering, and no power brakes). I hope this helps. My regular mechanic was away at the time, but when I mentioned the symptoms to him after having it repaired, he told me it was probably the vacuum pump. If he had been around at the time, I would not have had to pay the additional $180 or so for the diagnostic tests.