Just picked up my 99 S420 from the dealer for checkup on overheating and low oil ps. They chnged the oil pressure sensor, oil pump and oil change. The oil pressure flies to 3 immediately but it still drops to two. My oil was definitely the problem because I change oil at 1,500 intervals because I put about 2700 miles a year since I bought it. I had the coolant changed 2 weeks ago and now the car is overheating to 100 C (does not stay at 80 anymore) so I told the advisor to fix it. They tested the car for forty miles and performed a roartest twice and they say it is constant at 84C.

99 s420 45000mi
97 e320 37000mi
89 300e mileage unknown (got stuck at 93k)