Do I have an Oil Pressure issue?

My car has been PERFECT since I got it 5k miles ago, now has 36k. I just noticed this AM and just now tonight again, that during startup thru warmup (180) that oil pressure was reading about 4.5+ It has never been that high at that point, it also seemed to run high during low speed excelleration. Went to the store and car was warmed up PLENTY. After I came back out, it seemed to run the normal 3.5 at speed. Since I have never seen it do this or run this high and it has consistently clocked the exact same pressure numbers since I got it, do I have an issue waiting in the wings or is it No Big deal? Thanks

Sounds like you HAD an issue before now. Here is what the typlical 996 oil pressure gauge should read at various points of opertion. Cold engine at all engine speeds: 5 bar Warm engine at idle: no less than 1.5 bar Warm engine above 3000 rpm: 4 bar+

Higher oil pressure as my engine gets older is a problem I would be willing to put up with!

I disagree with "no less than 1.5 bar" when warm at idle. I'm just under 1.5 (maybe 1.4) and that's fine. Nothing to worry about.

Mine runs the same as 1999Porsche911's. Did you recently change oil?

Bet you're running Mobil Water(oW40) and/or your coolant temp exceeds 215f.

Gauge stays at 180 and, yes, I'm running what Porsche recommends.

If your gauge stays at the kine for the 180 mark, it is broken. Target temp established by Posche is 90C but the car cannot run that cool in warm temps driving around town unless you do my fan mod. Without it, your coolant temp regularly hit 215F+. NOTE: Mobil Water is NOT recommended by Porsche....only approved.

Sounds like your oil pressure is normal. Occasionally, when stopping barely above idle on a steep hill, my oil pressure will drop low enough for the oil pressure warning to come on. Now that is something that will get your attention. Never thought much about it since at the time I was running a low level of oil on the dip stick, and it recovers quickly. More of an idle too low problem would be more accurate. Tom L 2002 C2

Depends on what the meaning of "is" is...

Yeah, it is. Don't have my manual handy but pretty sure the manual shows pressure below 1.5 at idle when warm...

Doesn't get that hot here in Greenwich, CT. I'm sure my gauge is just fine.

So, are you saying that coolant stays at 180? Not possible. (Bytheway, I grew up where you live). Your car cannot maintain 180F. Even in winter it is hotter than 180F. I suggest that you hook up a scanner and take a look at your actual engine temp, or use the diagnostic display on the climate control panel. Your coolant temp will surprise you when you see it as hot as it actually is. The Porsche gauge is meaningless as far as displaying actual temperature. Once you figure out the correlation to the temperture needle and the actual temperature, it is consistant, however.

I have the Durametric software. I think I can see it with that. I'll take a look. Thanks for the tip.

I was actually seaching the same topics yesterday. Most people run around 4-5bar at 3000RPM+. Mine is at 4-5 bar pretty much anytime the car is driving. It idles at the light ~ 2.5 bar.

2.5 bar when idling? what kind of oil do u use?

no, your manual won't tell u about idling oil pressure.

I had the whole car gone over after I picked it up in St. Louis, this included an oil change with the "water" oil. I have done nothing since. I watched it again this AM, as soon as I start it up, it goes to 4.5+ and stays there whether I am driving or idling. Sounds like others have it the same, but for me, it has NEVER registered this way. It never made it to full temp before I hit the gym. After leaving, get back in car and it tops out at 3.5 at idle???? Its acting normal after everything gets warmed up, but the 4.5+ is not what I have been experiencing. Could the start of colder weather in the past couple of days cause this? Cincinnati AM temps have been low 50's? Just want to make sure I am not driving and causing an issue! Thanks

Queens city - it sounds like your car isnt fully warmed up, so your 3.5 at idle on a cold car sounds right. Remember as oil warms it becomes less viscous (and there are 9.25 qts of oil in the m96 engine). I posted a similair question a few weeks ago, I was getting ~3.5 >4K RPM, and 1-1.25 bar at idle. While not uncommon, the answer seems to be from the weight of the oil... 0w40 just seems to get to thin for these engines. I am running 15w50 now, and I get 1.5 when car is HOT at idle, and >4 bar when >~4K RPM. I have a feeling that you are going to see dealers go back to 15w50, the original factory fill...0w40w is too thin for these engines.

Check your oil level. Low oil will cause low pressure and and overfill will cause high pressure. Your pressure should be as I stated earlier. A warm engine is one that has been driven for more than 20 minutes. What year car do you have, anyway? If you are not above 4 bar in pressure when driving a warm engine, you may either be low on oil or it may even be a bad oil sending unit.

Whats actually happening now, as opposed to all of the other days in the first 4 months, is that it is 4.5+ at speed AND idle. It has never done that, it would at least drop down a bit at idle. It now stays at 4.5+. It does go to 1.5 at idle like it used to when warm. I did check my oil level and its right on the money. The car is a 2001. It is going to 3.5 + at 4k RPM or cruising speed, so all is still good there. I am thinking since the "problem" just started and the weather just started to turn, that that is the cause. Its just that I have never seen it go to 4.5+ at startup and stay there whether cruising or idling until warm. I just dont want to screw the darn thing up. Could it be the gauge is starting to go bad???

Regardless of the ambient temperature, once the engine is warmed up, the pressure guidlines I stated earlier still apply. If you are getting a change in reading, I would first look at the oil sending unit. You may have a bad ground or need a new unit. They do go bad at times and it is not a big deal to replace. Not having pressure above 4 bar when cruising above 3000 rpm is unlikely mechanically, so sending unit or gauge would be my guess.

agreed - sounds like something silly.... not engine related. my 0.02

mine in south texas on a 100+ degree day gets as low as 0.8 bar at idle with 15W-50 weight mobil one

That's because your engine is running extremely hot. In 100F+ temps, without modding the radiator fans to keep the coolant below 200F, your engine temps is exceeding 220F while driving below 60 mph. Do the fan mod and you can drive all day long with engine temps below 200F. In tests that I have conducted in 103F temps using 15W50, I was unable to get the oil pressure below 1.3 bar (using a calibrated, inline pressure gauge). This was even letting the engine temp get to 230F and idle of 800. Removing 1 quart of oil from the engine made the pressure drop by .3 bar in same conditions. Those with idle below 800 will experience slighty less pressure.

to all for the info!!!

Wanted to know if you fixed the problem? I have a 2000 996 with the same problem.

Thicker oil will indeed give you a higher oil pressure reading but the normalized flow (hot) should not change, just the pressure that is generated from pumping it! Motor protection is dependant on the volume of oil pumped to the surfaces which are cooled and lubricated by that volume, not pressure...if you feel better seeing a higher oil pressure on your gauge, thats OK, just be aware that pressure is no indictation of an oil doing any better at protecting things. Lubrication protection is determined by volume, not pressure.

I switched to moble (water) 0w-40 with same high oil preasure readings. I don't want to create a RMS problems.

That's exactly what my mech. says with the miles I have I need oil flow not pressure and he recommended 5w30 and I never have a problem. fwiw he's owned and worked or these cars since 74.

2fasfu, there are very few (if any) 5w30's that will meet the HTHS (high temp high shear) specs that are required for these engines...need an HTHS of 3.6 or higher...Redline 5w30 may meet it...You would be better served with a 0 or 5w40 synthetic. Just an FYI....

Part of that is simply not true. Proper pressure is critical. The plain journal bearings used on the crankshaft, etc. in a normal automobile motor are supported by a surfboard type hydroplaning effect and require oil pumped in under sufficient pressure to keep this happening before the oil blows out the ends of the bearing. Everything here is designed as a system, bearing width, bearing clearance, oil viscosity, and pressure. Without enough oil pressure feeding the bearing, the journal will collapse through the oil film and you'll have metal-to-metal contact. If this happens under load the engine is lunched rapidly (spun bearing, thrown rod, etc). Too thick of an oil won't flow freely under the same pressures. And will cause all sorts of other problems in areas that are lubricated by splash and gravity. Bill

wrljet, I will clarify...I was making the assumption that there were no internal problems and that the oil pump and lines were operating correcly...we do need pressure for the reasons you stated. Higher than normal pressure is not needed given an engine that is "in spec" and in some cases it can be detrimental. An engine that has pressure in the "normal" range shouldn't suffer from oil film collapse as long as it is in spec. Would you agree?

bgiere, yes I agree with that.

I do a little too much reading on this issue,but there is an oil guru named Doug Hillary who has a handle on Porsche oil specifics...I read all that I can find from him...He used to be a regular on Bobistheoilguy.com and occasionally posts here on Rennlist...I must credit him with most of my knowledge...the stuff I'm wrong on is usually my own!!

I have an oil pressure issue with my car. The gauge now reads 1 when it should be 0. I assume it's the sending unit, but haven't looked into it yet.

What is the 'diagnostic display on the climate control panel' and how does it work? Sorry if this is a dumb question! Ian

Installed a new oil pressure sender, 54$ 996-606-203-00-M100. Oil pressure back to normal! A 19mm 45 degree angle wrench would have made it a very easy to change.

My gauge was pegging between 4.5 and 5 at only 2-3k rpm and the dealer is now replacing the oil pressure gauge....warrantied but I was told it is a $1400 job...I was shocked. The dealer blew me off the first time I mentioned I thought the sending unit or gauge were off......look to see if the gauge is reading even without the car being turned on....mine was.

sounds like a sending unit not a guage but guage is possible

Mine sticks at 4.7-5 while driving... idles around 2. Stuck at 5 while warming up driving. Had a recent PPI done... compression/leakdown pegged the charts all six cylinders. '02 w/ now 32K miles. 0w/40 Mobil 1.

Check part 23 and 24. I had replaced sping for no oil pressuer. Easy check, piston should slip out easy, could be jamed... not sure if possible. Do some reading on the oil pressure regulator. http://www.pelicanparts.com/PartsLoo...-00-Frame3.htm Chris