My car has 102,000 miles. It has the 4.0 V-8 North Star motor. I checked the oil and it was down a little over a quart. I added a quart of Valvoline High Mileage 10w-40, this is the same oil and weight I have always used. When I drove the car, my oil pressure started to randomly read zero, then shoot up to 125lbs and then be fine for awhile. The readout would repeat this over and over again. It's still doing this, it has been going on for about 2 weeks now. I have never had this experience before and I am 70 years old. I have owned, now 5 Auroras since 1994. My first one had over 300,000 miles on it when I bought my second one, never have I had this experience with any of them. My mechanic can't explain it either.