tangram

Having checked the archives and not finding my particular problem discussed, I pose this question to my knowledgeable fellow Rennlisters. I just finished a two-day, 700 mile tour where we drove the car hard for eight hours each day in temperatures approaching 95 degrees. About 6 hours into Day 2, I noticed my oil pressure gauge acting erratically. At times, the needle would drop into the lower red zone, at other times it would settle in around the 3 mark (with 5 being max). Unlike most owners with pressure gauge problems, the needle was not pegged at max. Whether at idle or cruising speed, the erratic behaviour persisted. Oil temperatures remained low, and oil levels were good (as per dipstick reading).

I was trying to ascertain what could cause this problem with the gauge. I guess there could be an electrical short. I don't think it is the sender judging by the difference in my problem vs. others. Are there any oil pumps in the car that could be malfunctioning? Clogged filters (last oil change 2,500 miles ago). I'm puzzled by the fact that oil temps remained low and the levels were good. Please excuse my ignorance, as I'm in no way a gearhead, just somebody who enjoys driving!

Dick in TN

With the pressure jumping around like it is, most likely it's a bad sending unit or gauge. A short would totally disable the gauge, although an intermittant short could also give erratic readings.
Porsche oil filters have a bypass valve that allows oil to flow if they become clogged, impossible at 2500 mi. anyway. There are two oil pumps which almost never fail, and if one did, you would have a blown engine in a matter of minutes.