I have several problems which may or may not be related.

First I have a 1992 190E with 208K miles and I am using a 20-50W oil.

1. Oil pressure gauges shows ZERO on idle. The benz runs fine. When I accelerate, it goes to 3. I wonder if the oil pressure sending unit is the cause? What do you think?

2. My benz seems go to high temps quickly. From a cold start then drive for 10minutes the temp goes to 100 deg. When I drive on the freeway, no traffic and going 65mph, temp is about 98/99. I expect it to be 90-94.

Also, my fans (dual smaller fans) don't engage at 100. It use to engage at 100. Now it engages at 110.

I did change a sensor related to my fan being constantly on. That fixed the problem way back (about a year ago).