Have the tires pulled and put on a balance machine. Sounds as if some belts within the tire/tires may have shifted. On my 190E 2.3 16V, it was smooth as glass until I hit about 60 mph, which doesn't take long. At that point, it felt like a bent rim. Turned out to be a shifted belt on one rear tire. Have the tire guy look for the rim to wobble or watch to see if the tire is wobbling.
Good Luck,
Jayare
PS. You may want to visit the W201 forum. That's where 190E owners live. Never the less, welcome
Good Luck,
Jayare
PS. You may want to visit the W201 forum. That's where 190E owners live. Never the less, welcome