Jump to content

Server Lease Renewal/Software Licenses

Our yearly server lease, software licenses, as well as hardware operating costs, ARE due Dec 6th, 2021. Our current donations have fallen far short of the funds we need to renew. Please remember the RennTech.org community is Member supported so please consider a donation to help...  THANK YOU!

Welcome to RennTech.org Community, Guest

There are many great features available to you once you register at RennTech.org
You are free to view posts here, but you must log in to reply to existing posts, or to start your own new topic. Like most online communities, there are costs involved to maintain a site like this - so we encourage our members to donate. All donations go to the costs operating and maintaining this site. We prefer that guests take part in our community and we offer a lot in return to those willing to join our corner of the Porsche world. This site is 99 percent member supported (less than 1 percent comes from advertising) - so please consider an annual donation to keep this site running.

Here are some of the features available - once you register at RennTech.org

  • View Classified Ads
  • DIY Tutorials
  • Porsche TSB Listings (limited)
  • VIN Decoder
  • Special Offers
  • OBD II P-Codes
  • Paint Codes
  • Registry
  • Videos System
  • View Reviews
  • and get rid of this welcome message

It takes just a few minutes to register, and it's FREE

Contributing Members also get these additional benefits:
(you become a Contributing Member by donating money to the operation of this site)

  • No ads - advertisements are removed
  • Access the Contributors Only Forum
  • Contributing Members Only Downloads
  • Send attachments with PMs
  • All image/file storage limits are substantially increased for all Contributing Members
  • Option Codes Lookup
  • VIN Option Lookups (limited)

Recommended Posts

Lets start when I start the car 1999 996 Cab. The oil pressure shows just above 4.0 once car is in normal temp to drive 180. Outside temp 75 or so. Oil pressure is about 3.0 when ouside temp over 85 oil pressure drops to 2 or so. When at idle pressure drop under 1.0 Need to know what I can do before it ruins my engine. car has about 140k let me know if anyone has this problem and can help. Thanks

Link to comment
Share on other sites

IMO this is completly normal and well withing the limits of acceptable. - as long as it doesnt go below 1/2 at idle I would not worry - your car moves a ton of oil around..almost more than any other car out there... it is not an issue to see these numbers...

Link to comment
Share on other sites

This is the note from the MY03 Carrera Owner's Manual (page 80):

"With a warmed-up engine and at a speed of

5000 rpm, the engine oil pressure should be

approx. 3.5 bar."

I would imagine the above note would apply to your engine (MY99/3.4 litre vs. MY03/3.6 litre) as well.


Edited by whall
Link to comment
Share on other sites

AT 3000rpm its about 2.5 to 3 same for 5000

Apart from idle, you don't mention revs, which would give a much better indication if there is a problem. What pressures do you get with the water temp at 180, outside temp 80 or so, at 3000rpm and 5000rpm?
Link to comment
Share on other sites

  • Admin

A car 10 year old car with 140,000 miles will not have like new oil pressure - everything is somewhat worn.

If you are using 0W-40 or 0W-50 oil I think your oil pressures are about right for a 140k engine.

Depending on how you drive and handle maintenance you could get another 100k out of this car (or more).

All IMHO of course.

Link to comment
Share on other sites

I have only seen two M96.01 engines stripped down, and what surprised me (although the rebuilder said it was common) was that the bearing journals and shells, pistons and rings, were in remarkably good shape. I haven't searched here, but I don't recall many incidences of low oil pressure. Personally, I think 2.5-3.0 bar at 5000rpm is low. That's only 37-45psi.

So if it is unacceptably low there can be 3 causes. Leaks, wear, or that the oil pump isn't producing pressure. If it was me, I would look into changing the oil pump pressure relief valve piston and spring, as the parts are cheap, and I think it can be done on the car. According to the manual, the engine has to be reemoved to change the oil pump, but someone else here may know if it is possible to do on the car, as that would be my next thought.

You don't say what oil you use, but if you can't get the pressure up any other way, you might consider changing to a heavier weight 10W-50 or 15W-50. You might want to do that anyway, with the mileage you have. I think that is what Loren may be intimating.

Link to comment
Share on other sites

  • 1 year later...

my pressured dropped to 0.8 at idle with a hot engine, this was with 0W40 oil.

I got a little worried and have changed my oil to mobil1 5W50, now I have a pressure of 1,8 bar with a warm engine, about 1.3 with a VERY hot engine on a hot day. Much better. But now pressure is at the maximum of the scale, 5, when revs are > 2500 RPM..

Is that too high? Will it destroy oil seals?

Link to comment
Share on other sites

  • 2 weeks later...

interesting conversation. I just replaced oil pressure sender on my 996c4s 2003 and strangely at frist it read 5 even at idle. (no i didnt accidentally swapped wires) only after i took car for a test drive and revved it up to (almost) redline pressure started showing 3-5 depending on revs and around 2 at idle. is this normal?

Link to comment
Share on other sites

  • 2 weeks later...

Well, I was a little worried too, because I own the car for 2 weeks now, and my pressure when engine is hot (above 95C) drops to 0.5 and even below. But what I've noticed is that when I start it cold the arrow goes little below 4 and stays there even if I rev the engine to 3k rpm. It is like stuck at just below 4. That makes me conclude that the gauge is mis calibrated and the arrow shows the actual value -1. I have no warning lights and I have gone to diagnostics before buying the car and at Porsche service they haven't found any errors.

Link to comment
Share on other sites

There are two possible indication problems. The first concerns the oil pressure transmitter. It is the usual culprit and the least expensive to remedy. The other is the gauge in the instrument cluster. With the ignition switch on the "OFF" position, the oil pressure gauge needle shold be below the 0 point of the gauge....about a millimeter below. With the ignition switch in the "ON" position (with the engine static) the nedle should move to the 0 point. If this isn't the case - and the previous owner hadn't replaced the instrument cluster faces (incorrectly re-indexing the oil pressure needle) - you probably have a bad instrument cluster.

Because the oil pressure "idiot light" is the final arbitor when determining whether or not there is sufficient oil pressure - and it is not illuminated - you probably have oil pressure. To be on the safe side I'd suggest taking the car in and have a technician put a direct reading gauge on the engine. BTW, the Boxster/Cayman series has no oil pressure gauge, relying solely on the idiot light.


Edited by whall
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.