I was out driving in my car and heard a funny noise over behind the glove box. Kind of a muffled buzz. Then it stopped and the oil pressure gauge was reading zip. If I raced the engine a bit it would go up to about 1.5. I have full synthetic in it and the level of oil is correct. When I loosen the oil cover at idle there is oil flying all around. The car is running at a cool 80 degrees and idles around 800? What went?

Most likely an electrical issue... You can test the gauge in the dash by disconnecting the oil pressure sender wire (attached by the oil filter) and grounding it. Gauge should peg to 3 instantly. If it does, then the sender may be bad....they do fail from time to time.

__________________
-diesel is not just a fuel, its a way of life-
'15 GLK250 Bluetec 118k - mine - (OC-123,800)
'17 Metris(VITO!) - 37k - wifes (OC-41k)
'09 Sprinter 3500 Winnebago View - 62k (OC - 67k)
'13 ML350 Bluetec - 95k - dad's (OC-98k)
'01 SL500 - 103k(km) - dad's (OC-110,000km)
'16 E400 4matic Sedan - 148k - Brothers (OC-155k)

My thoughts exactly, same car, had the same issue. Replacing the sender unit only takes about 15 minutes. As far as the buzzing, that's nothing other than the little fan behind the passenger side air vent. It sucks in air to get the cabin temp to adjust the ccu.

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1990 190E 3.0L

If the CCU fan behind the glove box (actually next to it beneath the passenger side vent) starts to annoy you, you can remove the interior of the glove box (pop out the plastic 2-piece tabs, remove latch strike and pull forward, its right on the lower right, can unplug its connector easily.

__________________
-diesel is not just a fuel, its a way of life-
'15 GLK250 Bluetec 118k - mine - (OC-123,800)
'17 Metris(VITO!) - 37k - wifes (OC-41k)
'09 Sprinter 3500 Winnebago View - 62k (OC - 67k)
'13 ML350 Bluetec - 95k - dad's (OC-98k)
'01 SL500 - 103k(km) - dad's (OC-110,000km)
'16 E400 4matic Sedan - 148k - Brothers (OC-155k)