Vacuum adjustments 1995 W124 E320

[ksing44]

After searching and reading through many posts on the forums, I am pretty convinced that I must have a problem with too much vacuum. The symptoms include a shift flair with 3rd to 4th gear shifts and a slapping air vent on start-up. It all started after I had my transmission flushed, all seals replaced, and had the Bowden cable replaced.

My real problem is that the dealer seemed to be ignorant about how to fix the issue, even though they seemed to have caused it with their repair. To their credit, or harm, the shop foreman did come out to talk to me and he admitted that they don’t really have many or any mechanics that are really very knowledgeable about my car. He said that many of the new mechanics were more oriented toward understanding the electronics of the new cars. This problem, and a couple more, along with the foreman’s comments, was what had me thinking I should just ditch the car, but I just couldn’t give it up. I love the thing!

So what do I do? How can I get this fixed before it actually hurts my transmission or my air handling system? I think my Indy might be able to figure it out, well maybe one of their fathers that started the business, but I think it would help if I could point the way. I am hoping to get some expert tips about the things to adjust and/or replace.

I did find quite a bit of discussion about vacuum modulators down on the transmission and also some things about a K1 kit for inside the transmission, but the conversations were virtually all in reference to diesels. In fact it seemed like some of the stuff may have been specific to only diesels.

The actual questions:
1. Could the 3rd to 4th shift flair and the slapping vent both be caused from too much vacuum?
2. How can I adjust the vacuum?
3. Does a 1995 E320 gas engine have a vacuum modulator like the diesels?
4. If I have a vacuum modulator, does it control the vacuum for the entire system, or just the transmission?
5. Do you guys have any other ideas?

Thank you