Well I figured the filters were likely to be pretty dirty anyway since they have not been replaced since we have owned the car.

We did try all the sliders, I even shined a flashlight in there to be sure I could see how the dampers were moving as I moved them. Like someone else here said, there are 3 positions, full open, almost closed and fully closed. No luck there.

I was checking out alldatadiy.com last night but the site may have been having a problem because all the fields were blank no matter what type of car I typed in. I would like to find out how much work its going to be to replace some vacuum elements. Maybe get a vacuum tester but I have never used one and at the moment dont see how they are used to actually locate a vacuum leak. Please keep the ideas coming.

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1996 E320
2000 C230 Kompressor
1988 190e 2.3 - 225K miles, owned for 7 years. I cannot say enough good things about this car. Very well built, even at 225 it ran like new.