kimo964

A friend of mine just purchased his first Porsche, a 91 C2, yesterday and wanted to get my opinon on it. 34K miles, one owner, fully optioned, 30K service done, dual flymass/clutch done for $19K. Just need a little exterior and interior TLC. He bought it w/o a PPI because of all the receipts. My only concern was his oil pressure. At idle it's between 1 and 2. At speed, it's at 4. My 89 C4 idles between 2 and 3. It's tacked at 5 at cruising speed. Does he have anything to worry about....or do I? What's normal or is every 964 different? TIA

Computamedic

Hi,

You don't mention whether the engine is hot or cold but I'll assume it's hot since you wouldn't expect any meaningful oil pressure figure when it was cold.

The figures you quote for your friend's car seem perfectly normal to me - compared to my 89 C4 which is almost identical. If my car gets over the 8 o'clock temperature it will drop to 1 on idle but rarely exceeds 4 at speed.

I would be very suspicious of your readings - I would guess your gauge is faulty or the sender is on the blink. I would never expect to see 2-3 on tickover unless it was a very cold engine.

Hope that helps,


Best regards

Dave

Bill Wagner

You need to compare results at similar temps with IDENTICAL oil viscocities for the comparisons to be of any meaning.....and I'm talking about engine temps when fully warmed up.

Unlike water cooled cars, the 964s temps will vary considerably with the outside temperature and engine temp. For example, two weeks ago the outside temp was fairly cool and it was raining, and fully warmed up my guage was reading about 2 at idle. Last week, the outside temp was hot, and at idle my car came in about about 1.5. On the cool day, my engine temp was just below the 8:00 postion on the engine temp guage, and on the hot day it was slightly above the 8:00 postion.

Readings will ALSO depend on the viscocity of the oil. I run 15W-50 on my 964, but if I was running something like 10W-40, I would expect the pressure to be noticeably lower.

Hope this helps,

DaveK

Oil pressure seems to vary quite a bit between cars. But idle pressure between 1 & 2 is quite common (mine is only about 1.2 at normal temp). Mine is usually about 4.5 at speed I think - but as long as it's at least 4 I don't think you have anything to worry about.

kimo964

The car was driven about an hour on the freeway before he came by and he was idling for about 15 minutes. So the engine was warmed. I'll have him register since he'll have tons of newbie questions. Thanks fellas.

Arjan B.

Mine has with 0W40 oil and a hot engine a oil pressure from 1,2 bars. If the engine is just warmed up, the pressure is in idle 2.0 bars. At all times the pressure is max [5] with 3>>4 000 rpm.
It changed when I replaced my oil pressure sender, before that, the idel pressure was 0,2 higher.

No worries needed!