27 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCHOil pressure at idle in traffic - low? Normal?
Reported or suspected cause
gone
Reported cause
No successful repair reported for this finding.
1
Identified cause
0
Suspected cause
0
Reported fixes
Read evidence and context
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that report identifying a cause
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Leading evidence: 'gone' (1 discussions report identifying this cause; no attributable repair resolution). Across 1 matching discussions, the most frequently mentioned possible cause is 'gone' (1 discussions; 1 report identifying it and 0 suggest it). The most frequently discussed action is 'Check oil' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
Source reports, not a diagnosis or a success probability. Counts refer to discussions and can overlap.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that report identifying a cause
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Reported cause
The variation is caused by the normal variation in engine temperature.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that performed work without a confirmed outcome
1
Discussions that contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Performed · outcome unconfirmed
I found the cause...Too much oil...I changed the oil a week or so ago and my "helper" checked the oil with the dipstick and said it was perfect.
Install real coolant temperature gage and it was interesting
Performed · outcome unconfirmed
No successful repair reported for this finding.
0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that performed work without a confirmed outcome
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Performed · outcome unconfirmed
(I also installed a real coolant temperature gage and it was interesting to see how dynamic the coolant temperature was.)
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that performed work without a confirmed outcome
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Performed · outcome unconfirmed
Eventually all of mine have been replaced, but the issue wihich gave me the most problems was the fact that a brand new Porsche engine earth strap was already faulty when it was fitted.
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion
If you get the red oil can "idiot light" and on board cpu shows an oil can and text says "Engine oil pressure too low" stop immediately check oil level with on-board cpu and, if necessary, add engine oil.
Discussions that performed work without a confirmed outcome
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Performed · outcome unconfirmed
Eventually all of mine have been replaced, but the issue wihich gave me the most problems was the fact that a brand new Porsche engine earth strap was already faulty when it was fitted.
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion
At normal idle - mine will be just below 2 bar (with AC on) - and could get as low as 1.5bar on hot day (>80F) - only if I have been driving on hard run will it idle close to 1 bar ...(M1 0W40) ...
Counts describe captured discussions, not unique people or a diagnosis. Author identities are not reliably stored. Exact duplicate evidence is counted once across matching discussions; one discussion counts at most once per action/state. Multiple repairs reported together remain a combination. Suggestions and failed attempts do not establish a fix. Matches cover whole discussions and can include related faults, model variants and incomplete threads.
27 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
Rennlist: 1 discussions
0 evidence records excluded for query context · 0 excluded by outcome qualification · 0 adjusted by outcome qualification.
2 acknowledgements have no verified action link; they do not establish a repair result.
I have searched for two days and I am not sure I found a thread that addressed my question:
So I replaced my oil pressure sender unit 2 weeks ago, the pressure unit was going hay wire, but when I bought the vehicle it typically sat at 1.5, but didn't drive it in traffic. So i have been in traffic lately, about 15 minutes of stop and go. I have a low temp LN thermostat, new water pump if that matters. I am seeing 1.4-1.5 bar during normal driving and at idle. But in traffic, the oil pressure drops to about 1.1-1.2 bar. I can see the water temp needle rise during this time but doesn't go much past the "0" in 180. Is this normal? I run Joe Gibbs 5-40.
Outdoor temperature was 77F.
Thanks
At normal idle - mine will be just below 2 bar (with AC on) - and could get as low as 1.5bar on hot day (>80F) - only if I have been driving on hard run will it idle close to 1 bar ...(M1 0W40) ... so I guess just above 1 bar is OK ..
Unfortunately, the oil pressure gage is about as accurate and as precise as the coolant temperature gage.
Really it is an idiot light with animation.
If one puts any credence into the gage's reading (and if you do you are not alone for I still look at the oil pressure gage in my Turbo), what you are seeing is normal.
I have observed hot idle oil pressure ranging from 2 bar to nearly 1.5 bar.
The variation is caused by the normal variation in engine temperature. If one observes this in real time he can see coolant temperature going up and down. Having the A/C on dampens this up and down business some.
The times the oil pressure is "high" at hot idle is when the engine is a bit cooler.
The times the oil pressure is "low" at hot idle is when the engine is a bit warmer.
Study your owners manual and learn where the low oil pressure warning light is. If you ever see this come on the engine has an oil pressure problem. Now it may just be due to a bad sensor, but it may not be, so you have to treat it as a real problem with oil pressure.
Shut off the engine as soon as you can and leave it off until you get this sorted.
Have to say though if the oil pressure is really low you will probably hear bad sounds before you can get the engine shut off.
A total loss of oil pressure is rare though so I'd not lose any sleep over this possibility.
When hot in traffic congestion, and at idle, I think thats about what most are seeing. Macs correct, only a good mechanical gauge would prove it.
The most important thing is that you are using the right oil. Your engine will be fine and is very well protected. You probably eliminated 99.9% of the known MOF just by your oil selection.
Lots of variables in play with oil pressure - remember it's a fluid being pumped around at varying temperatures and loads.
Without a proper gauge and a more thorough analysis it's tough to say, but what you describe is normal: higher oil pressure when the engine is relatively cool and lower pressure at idle when the engine is relatively warm.
Nothing to worry about.
Depending upon various factors oil pressure can be rather high/elevated at RPMs above 2K. Above 2K RPMs I have observed around 4 bar at various times in my car even with the engine up to temperature.
The factory manual calls for approx. 6.5 bar at 5K RPMs and 90C oil temperature.
However, the highest I've seen the gage go is around 4.5 bar. I do not think the gage even has a 6 bar hash mark. There is a 5 and that's it.
My point is the gage and what have you is probably geared to once the oil pressure climbs some to just kind of get to what Porsche thinks is the most comforting level and remain there. On the other end of the spectrum Porsche probably has arranged things so the gage won't register the actual true peak oil pressures.
BTW, years ago I installed a real oil pressure gage in a car of mine (an early '70's Datsun 510) and I can recall how animated that oil gage needle was. With no dampening the oil pressure needle was moving all over that gage face. For most drivers I think this active of an oil pressure gage would be a distraction which is probably why the oil pressure gages in these cars is dampened as much as they are.
(I also installed a real coolant temperature gage and it was interesting to see how dynamic the coolant temperature was.)
If you are seeing abnormally high oil pressure at hot idle or if the oil pressure needle pegs at the top when the engine is fully up to temperature at RPMs under 3K there might be an oil pressure sensor or gage problem. But you would need this confirmed by a qualified tech.
As of late, after driving for awhile (say 30 mins or so) with the oil hot. Occasionally I get the low oil pressure indicator alarm at idle when i come to a stop. engine idles at about 750-800 rpms and I have about 3/4 of a BAR of oil pressure. It seems that across the entire range the oil pressure is low by about 1/2 a BAR or so. I am wondering if it is possible that the oil pressure sending unit can gradually go out of calibration? Every time the alarm comes on it scares the hell out of me for obvious reasons. I feel relatively confident that I have good oil pressure (engine sounds fine it idle, gauge moves over the entire range while I am driving at different rpms, etc)
Anyone got any thoughts? I am about to order the sending unit to rule that out.
I think normal oil pressure after fully warm up (like 1/2 hr in stop and go traffic) should be 1.5bar or more for 5w-40 oil. When the sending unit starts to act up, usually it goes to zero momentarily (or it flutuates up and down) during driving and not offset constantly throughout the range. However, it's good to eliminate a cheap and often failing component first.
What does it read when it's key on engine off? A good sensor should read 0 and a bad one may read 0.5-1 bar.
Btw, have you checked the oil filter for debris?
When mine went bad, as Ahsai says, it would bounce up and down while engine running. When it started throwing the oil pressure indicator warning and stayed at @ 2 bars with engine off, I had it changed. That fixed the problem. Prior to acting up the pressure was unrealistically high at most times, always 4.0 to 5 bars regardless of engine temperature.
2005 996 C4S
I just want to make sure mine is reading something, don't really know or care about the numbers. It would be nice, just thinking out loud, if it had a built in oil filter bypass light, but that's more or less for my info when I'm warming it up.
I'd be more concerned if the gauge was at 0 and didn't move as the engine was revved up.
P.S. According to my owners manual: if you don't get a red "oil can" light and the text shows an oil can with the words "Failure indicator" the indicator is faulty. If you get the red oil can "idiot light" and on board cpu shows an oil can and text says "Engine oil pressure too low" stop immediately check oil level with on-board cpu and, if necessary, add engine oil.
Two different warnings. Scared the crap out of me, as well, until I read the above: pgs 95 and 96 in my owners manual.
Does anyone know how many pounds per sq inch a BAR is? Another question while we're on the oil topic is this. My electronic oil level gauge is EXTREMELY SENSITIVE. If the oil level on the stick is a 1/32 of an inch below the flat spot on the stick the electronic gauge shows its down by one rectangle. If the oil level on the stick is 1/32 inch above the flat spot on the stick the electronic level fills in all the rectangles on the gauge. If the oil level on the stick is PERFECT and I mean not the slightest above or below the top of the flat spot on the stick the electronic oil level gauge will read right at the upper arrow. It takes LESS than 1/4 quart in either direction for the electronic gauge to change one rectangle in either direction. Are all the electronic level gauges this sensitive?
For those of you who think that you have low oil pressure take a good look at your volt meter. If your volt meter is reading below 13.2V your oil pressure gauge will start to read low and will get worse the lower the voltage. If you are sitting in traffic your oil pressure will change as the AC kicks in and out for instance.
I have had recent problems with low voltage which would get as low as 12.5V and at this level would get inconsistent oil pressures around 1 bar at idle and around 3 bar when cruising at around 2500 rpm. Since sorting the electrics after warm up, at idle, I get a very solid, needle's width over 2 bar and a solid +4 bar at 2500 rpm. These pressures remain the same no matter how long or hard I have driven the car.
Food for thought perhaps?
Funky voltages can be a result of corroded ground connections throughout the car. These cars are getting to that age where some ground connections have been compromised by the enviroment. Played this game on my 78 928, my 70 914 My old Ford truck and I suspect soon this car.
Find them all, un-do the nut scrub with wire brush, spay with some WD-40 or what ever protectant tickles your fancy.
The cables also fail with corrosion between the connector and the wire itself. Eventually all of mine have been replaced, but the issue wihich gave me the most problems was the fact that a brand new Porsche engine earth strap was already faulty when it was fitted. Changed that and now a very nice 14.1V at start up.
Thanks to all for the info. I found the cause...Too much oil...I changed the oil a week or so ago and my "helper" checked the oil with the dipstick and said it was perfect. I checked it on the dash and it was full so i thought all was well. Turns out there was exactly one entire quart of oil in there and what I presume was happening was the oil was frothing and the bubbles were causing the oil pressure issue. Drained out the extra oil and issue is gone. Lesson learned: ALWAYS manually check the oil after anyone other than you checks the oil...
