The oil pressure gauge on my 1992 mercedes 300E suddenly dropped to zero while I was driving. The car was acting fine and the oil light was not on. I stopped, the oil was a quart low, I added a quart and when I started the car again it jumped up and then dropped back to zero. Then it jumped up again and dropped again. Then it just stayed at zero. The car is running normal and since it was and I wasn't far from home, I just went ahead and got it into the driveway.
What in the world could be wrong with this thing? Is it the gauge or something in the engine? I have always driven older cars and this is a new one for me. Of course, none of my other cars even had a guage for oil pressure. BTW, It has 175,000 miles and it has been maintained.
Help!