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Discussion Starter #1
From the manual:

"Under certain circumstances it is not possible to display the oil level. The reasons for this include:

Engine is cold
Vehicle has been stopped after full-load operation at high engine speeds
Engine oil temperature is too high
Open rear luggage compartment lid.
A message about this appears on the multifunction display.

Vehicle is level.
The engine is at operating temperature and has been stopped for at least one minute."


This seems to suggest that the engine should not be running when we take a level measurement. It also seems to suggest that the measurement will not be available unless we're at operating temperature.

However, I am able to see an oil level all the time. I turn my ignition on, scroll and select, and it shows the oil level. I start the car with then engine cold, and I get an oil level. While I'm driving with the engine at operating temperature, I can get an oil level.

So the combination of the car and the manual have confused me again. How, exactly, does the oil level measurement work?
 

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You want the reading while the engine is operating. This will keep the level correct while all possible parts of the engine are filled with oil.
 

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You want the reading while the engine is operating. This will keep the level correct while all possible parts of the engine are filled with oil.
The manual very clearly states that the reading should be taken with the engine at operating temperature but stopped for at least one minute. You can get readings with it running, but I wouldn’t trust them.
 

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Discussion Starter #5
Well, it is a dry sump, isn't it? So I imagined it might be practical to get a useful measurement running. And my motorcycle is a wet sump, and calls for the engine to be running to give a level.

I found it odd that the 718 would give a reading with it running, because elsewhere - say with the TPMS - they tell you that a reading is not available until conditions are met, and tell you what those conditions are.

Off it is. I guess that's why they recommend checking when getting gas - presumably you're at operating conditions, fairly level. You just have to remember to go look, with the ignition on, before you start it up.
 

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The oil level sensing system is interlocked with the rear trunk lid. If you open it, you will not be able to read oil level until it is closed and other conditions are met. 981 is the same.
 

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Agreed. but why? What does the rear trunk lid have to do with an accurate oil level?
The oil level sensing system is interlocked with the rear trunk lid. If you open it, you will not be able to read oil level until it is closed and other conditions are met. 981 is the same.
 

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I believe oil level is monitored continuously. If the level drops below a predetermined level your dash will light up RED and tell you to pull over and turn the engine off. That is a safety feature to keep you from blowing up your engine should it run low on oil. However, that is only a rough measurement since some of the oil is being pumped through the engine and in the process of running back down to the pickup point. Obviously to get an accurate measurement the oil must be warmed, so that it will indeed run back down to the bottom. And the engine must be off so that all the oil is down at the bottom of the pickup point where I'm assuming the device that measures the level is located. Anyway that is my guess.
 

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Agreed. but why? What does the rear trunk lid have to do with an accurate oil level?
Best I can come up with: The latch (or light switch) in the trunk is the easiest (cheapest) way for the ECU to know that you may have accessed the oil cap, and possibly added oil. The system then must cycle through the requirements that must be met to accurately show the oil level.

It's rather inconvenient.
 

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Best I can come up with: The latch (or light switch) in the trunk is the easiest (cheapest) way for the ECU to know that you may have accessed the oil cap, and possibly added oil. The system then must cycle through the requirements that must be met to accurately show the oil level.

It's rather inconvenient.
This is also what I have always been told. Opening the hatch causes the system to reset in the assumption that you just added oil, so you must close the hatch and wait 1 minute again to get a new reading. The Germans are known to over engineer things and make otherwise simple task more complicated than need be.

Take a look at the pdf document attached for more info. It's for the 981, but should still be somewhat relevant for the 718, and I assume this is what the systems are doing and why the OP can get oil readings when the car is running. This specific info in NOT in the manual if I recall, and I don't recall where this data came from specifically as I've had it stored on my PC for a few years. It looks like data from the digital "Good to know" app, but this very specific data as to how the oil levels are presented and why is not in my Porsche good to know app. Its very good info if still applicable, so I have no idea why this isnt being shared in the manual any longer
 

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