Dear Doctor: I own a 1997 Porsche Boxster with 50,000 miles. The oil light comes on after the car warms up. The moment the idle raises it goes away then comes back when the idle lowers (car in neutral). I replaced the pressure sensor. Could the oil pump be going bad? Ed
Dear Ed: It seems the oil pressure is dropping just enough to set the light at hot low-idle speed. The idle speed could be as little as 100 rpm too low. Also, the engine bearing clearance could be slightly more than original specification. My suggestion is to use 15/50 or 20/50 full-synthetic oil and see if the light stays out at hot idle. A slight amount of oil pump wear is also possible. If the light stays off with the oil replacement, then I would not do anything further.