Coolant tank pressure and strange oil pressure

[mpikounis]

Symptom #1

My MY03 996 cabriolet has been leaking a very small amount of coolant (I think) from the cap even though it is the newer part. I haven't had a chance to clean it properly and make sure it "clicks" when closed. Today, I opened the cap to clean it and noticed pressure being released. Not too much, but noticeable.

Symptom #2

During the past 2 months the on-board computer has reported an Oil Pressure Sensor Failure twice. The error went away both times after I switched the car off and on so I didn't pay too much attention. Today, whilst driving I noticed that the oil pressure during acceleration was at "5" and during idle at 3.5. It seemed as if pressure was higher than normal. Then, after accelerating hard (maybe relevant?) I noticed the oil pressure was back to normal, with idle pressure at 2-2.1 and 4.5 whilst accelerating.

The two symptoms got me a little bit worried. Am I being paranoid?

[Loren]

If you are really concerned you should drain the oil and look for signs of coolant.

If the oil is clean you can just put it back in.

[mpikounis]

Is symptom #1 normal for the 996? Can you think of any other reason why the coolant system would maintain higher pressure even when cold?

[Loren]

There should be very little pressure released when the car is cold. The pressure will vary as to how the car has sat without being run.

A leak is not normal.

[mpikounis]

Thank you Loren for your reply :D . If this is the case then I guess I can replace the oil pressure sensor (since it is inexpensive) and make sure the coolant tank cap closes properly and re-evaluate the symptoms. The leak I was referring to is absolutely minimal (go from a-little-below-max to min in two months) and I am almost certain it is from the cap.

Edited April 23, 2007 by mpikounis