Brett Jenkins

Monday, I hopped in my 85.5 944na, after it had sat overnight and fired it
up. I had no oil pressure! I immediately shut it off and popped the hood to
check the oil level. It had plenty on the stick, so I started it again, and
still had no pressure. I went ahead and added 1/2 quart of oil and started
it again. It still had no pressure, but after running 5-10 seconds, the
pressure jumped up to max and stayed there. I went ahead and drove cautiosly
for a bit, and after if had warmed up, the pressure about 2.5 bars. I
checked the oil again and it was full.

The next day, the same thing happened, no pressure. I just let it run for
10-20 seconds, clickety-clacking, and then the pressure jumped up to normal,
but again dropped to 2.5 bars or so after warming up.

Is my pump going? Do I have clogs? What else could it be?

Thanks in advance for any help.

HY M8NC

There have been a lot of threads on this, I figured out my problem (same thing) here as well.

My problem was a stuck oil pressure relief valve. This valve sits below the oil filter, in the oil cooler housing. Mine was sticking partially open, so the oil would drain out of the filter housing. I ended up taking the oil cooler off and using a hammer/punch to remove the old valve. There is an alignment tool that will help you line up this housing if you remove the cooler. I would start there.

Other possibilities
Non-Porsche oil filter allowing oil to leak out.
Oil pump not sealed well to the engine case, allowing oil to drain out of the pump.

My guess is the relief valve. Check the archives for the procedure-it's not terribly expensive...