"Hamsterdan" (love the user name!) I can't really address the stalling issue you have, but I "used" to have the same vibration issue. While changing the Timing belt on my wife's Mystique, I also changed the Left and Right Eng/Trans mounts, Serpentine belt, Tensioner, and Idler pulley. Car has 110K and idles smoothly in Drive now.
I'd suggest trying the Serpentine Belt, Tensioner, and Idler pulley first to try and resolve the vibration. They're the cheaper items. A serpentine belt with any kind of slack/whip can set up a pretty strong vibration. It may look like it's running smooth across the upper pulleys, but if you pull the lower splash-guard and look at it (running), you may notice how much it moves.
If you end up doing Eng/Trans mounts, check "Anchor" (
P/N 2873 ) Left/Driver's side trans mount prior to installing it. The one I got from Auto-Zoo was 3/8" off in the spread of the bolt holes that go into the inner fender apron. The bolt holes on top that mount the airbox bracket were the wrong size and needed to be drilled and tapped for the next larger size bolts. The latter may have been a year/model change problem.
Your Stalling issue might be related to the power steering pressure switch if it only seems to happen while the wheel is turned to any extreme.
