My 190e 2.6 leaked coolant briefly then stopped, my mech did the pressure test too, he checked it out and said it was a leaking waterpump but I noticed the car was no longer dripping coolant so I left it alone.

My E420 temp gauge goes up to 100-105 after just 5 minutes of idling, it bothers me but I'm kind of used to it bcuz my 190E used to do the same thing until a mech I took it to did something to make it stop, unfortunately I didn't bother to find out what he did back then since I just wanted the temp gauge to stay at 80, this was 5 years ago when I first bought my 190e and did not know this was considered normal in a Benz.

I've been told the high temp is normal but it still bugs me anyway, there are ways to fix it such as making the fans come on earlier since they don't kick in till 115 degrees but I don't want to tamper with this engine.

Let me know if you are interested in ways of lowering the temp and I can send you the link, sorry I couldn't be more help with the coolant issue.