Why does the oil level gauge take so long?
 

It's one of the most infuriating things about my 997. I am trying to check the oil level and the gauge has a time countdown clock that says it will be another 36 minutes before the oil level shows. What is all this about anyway? My poor dogs have to remain locked into their yard while I wait so I can lock the garage door and I am late for my run too :banghead:

In certain situations it may take 5 minutes or so...read the owner's manual - the process and requirements are explained there.

Well... oil has to migrate its way down to the pan and settle into the entire system as well. Only then can you get a reading. If the engine/oil is warm, you should be able to get a reading in just 2-3 minutes, since warm oil moves a lot easier/faster. Normally, I do a cold check (just before starting after sitting in garage overnight) and when fueling up, which takes a few minutes, I check then, too. Requires 2-3 minutes when I am refueling. Works out fine.

I find a level cold check matches my warm oil check when refueling every time.

Dipstick: If you have a car with less oil and a dipstick, you have to follow the same procedure anyway, but it might be shorter because it's a traditional sump and less oil.

The computer isn't slowing you down. This isn't a dipstick missing issue. This delay is physics, the type of sump system and the amount of oil in play. If you had a dipstick, you'd just be measuring the oil incorrectly, based on your desire to rush.

So... win for the computer... and the dipstickless measuring system... in this case.

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Yes I appreciate its probably a good system. What would make it better though is if the handbook stated the correct amount of oil to go into the engine as this problem only becomes tiresome at oil/filter change time - which is one of the only regular servicing jobs I do on the car myself. The amount of oil which officially is supposed to go in will not take it up to the max level. Then you have to top it up by trial and error to get it just right.
I put in 9 litres last week but it turns out this is too much so I had to drain some out. Finally (I hope) after five and a half years of owning the car I have established the precise oil capacity with filter change.

It is 8 litres + 350 milliliters.

Don't know what this converts to in US quarts but I suspect measuring in full quarts is still not precise enough to get the level just right.

Edit my car is a 2005 3.8 C2S

I still say read the owner's manual - lots of answers to your questions there.

Here's what it says about measuring:

The difference between the minimum and maximum
marks on the segment display is approx.
1.2 liters.
Each segment of the display corresponds to approx.
0.4 liter.

And capacities:
911 Carrera, 911 Carrera 4: Oil change quantity without oil filter approx. 8.5 quarts / 8.0 liters
911 Carrera, 911 Carrera 4: Oil change quantity with oil filter approx. 8.7 quarts / 8.25 liters
911 Carrera S, 911 Carrera 4S: Oil change quantity without oil filter approx. 8.7 quarts / 8.25 liters
911 Carrera S, 911 Carrera 4S: Oil change quantity with oil filter approx. 9 quarts / 8.5 liters
Please observe the chapter “ENGINE OIL” on Page 201.

The oil has to reach a certain operating temperature before an accurate reading can be displayed within 1-2 mins. Go drive the car, or check the oil after a trip not first thing in the morning.

36 minutes? Mine never took more than 50 seconds

I drain/change my oil quite warm/hot. I add 8L via Motul liter bottles and it falls right in the middle. I run that oil hot, then do a real check on the warm oil after it's settled. I usually then add a touch more and 90% of the time I am at the top of the acceptable range when checking the level.

Pretty much the same routine on all cars. Things that are different: Oil am't and time. 997 takes more oil; I think in terms of liters and everything takes more time due to system and volume.

The more I talk to people about oil changes and measurements, the more I believe the lack of a dipstick is a guardian against their misunderstandings. It's times like this that I see the Porsche thinking that removed the dipstick.
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Great point.

Checked at full operating temp, mine takes between 30 and 50 seconds to settle and read. 36 minutes doesn't make sense?

On a cold start with the car sitting for a while, it shows the oil level within a minute but if you're running around, stop and go again within a 30 minute period I've seen a status of over 1hr for the oil level to be displayed.

Questions is...why would you need to check your oil multiple times a day instead of just once in the morning?

My 2009 997.2 is different. The oil has to be above some hot temp, then sit at idle for about 1 minute. Blip the throttle, and you have to wait another minute.

If hot and one minute idle are not met, you don't get a reading.

Peace
Bruce in Philly

If you check before startup when it's cold it takes 4 seconds. If you start the engine and then check it takes 29 minutes.

With cold oil and just switching on the ignition without turning over the engine my 997 will give a reading within seconds. But this morning I had to move the car a short distance into my level floor garage - the only place on the property that I know is level to get an accurate reading as it had been reading over filled. Sometimes in the past this was due to the ground being not entirely level.

Never was good at physics so might be a stupid question but would the volume of the same quantity of oil change between cold and hot temperatures that might affect the reading?

But OP has a 997.1.

997.1 - check with engine off

997.2 - check with engine at idle

Not really. 8L of cold oil doesn't convert t 8.5L of hot oil, for example.

When cold and after sitting some long time (like overnight), the comp knows that X am't of oil should be in the pan. Easy peasy.

When you circulate the oil and shut it off less than hot, the comp has to buffer in extra time for that thicker oil to migrate down. So, it says, "let's give it plenty of time... like 30 minutes... to sink back down."

When you run the oil up to 200 and then park the car -- say to refuel -- that hot oil is flowing down to the pan. Its viscosity is 40 or 50 now. It's-a movin'. Computer knows it's hot and it knows that in a few minutes that X am't should be back in pan, so it can give a reading.

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