Oil Level Sensor - Response time?

[EarthboundMisfit]

How long does it take for the oil sensor in your car to report the crankcase oil level?

Mine is taking up to 10 minutes, which doesn't seem right (and I'm sure my last BMW took about a minute at most).

[jonasaurus]

Was the engine at operating temp?

[aussiem3]

Originally Posted by EarthboundMisfit

How long does it take for the oil sensor in your car to report the crankcase oil level?

Mine is taking up to 10 minutes, which doesn't seem right (and I'm sure my last BMW took about a minute at most).

It's normal on the ///3 to take a long time, and as the OP asked, the level will not show up until it has reached the operating temperature. At times I have driven for a very long time before reaching the optimum operating temp, and then it shows up.

The newer cars like the F25 X3 show up a lot quicker. Probably the sensors in the two cars work differently or the oil warms up a lot quicker in the X3.

[EarthboundMisfit]

Originally Posted by jonasaurus

Was the engine at operating temp?

I certainly notice the delay from a cold start, but can't recall if it's the same when the engine is warm.

If the sensor does require oil to be at operating temperature to make a reading, then that seems a bit flawed to me.

[jonasaurus]

Well when the engine is at opertaing temperature it takes less than 20 seconds typically, from cold I never tried but would be a while whilst stationary to get up to a temp it could take the reading.

[Jin-ActiveMotorwerke]

It is certainly not a flaw. It's more like precise engineering. You can probably say it's a bit too precise.

Oil density is dependant on oil temperature. And only at the right temperature can it measure the exact oil level it requires on M3/M5.

So the system is design to only read the oil level at oil temperature above 90 degree roughly. Nothing to do with the sensor it uses.

Originally Posted by EarthboundMisfit

I certainly notice the delay from a cold start, but can't recall if it's the same when the engine is warm.

If the sensor does require oil to be at operating temperature to make a reading, then that seems a bit flawed to me.

[EarthboundMisfit]

Originally Posted by aussiem3

It's normal on the ///3 to take a long time, and as the OP asked, the level will not show up until it has reached the operating temperature. At times I have driven for a very long time before reaching the optimum operating temp, and then it shows up.

The newer cars like the F25 X3 show up a lot quicker. Probably the sensors in the two cars work differently or the oil warms up a lot quicker in the X3.

I think you're right; seems it's normal behaviour.

I just checked the Owner's Handbook and it says:

"The oil level can be displayed when the engine is at operating temperature". Goes on to say a reading "can take about 1 minute if the car is at a standstill on a level surface, or about 5 minutes while the car is on the move".

Also says a rapid measurement can be taken by holding the BC button for at least 2 seconds when in the oil level display screen on the instrument cluster.

Thanks for the response.

[EarthboundMisfit]

Originally Posted by Jin.ActiveMotorwerke

It is certainly not a flaw. It's more like precise engineering. You can probably say it's a bit too precise.

Oil density is dependant on oil temperature. And only at the right temperature can it measure the exact oil level it requires on M3/M5.

So the system is design to only read the oil level at oil temperature above 90 degree roughly. Nothing to do with the sensor it uses.

Well, we can agree to disagree on what we think the flaws in our cars are, but it seems that it is normal for the sensor to take so long to read oil level.

Digressing slightly, I think BMW's intent (in this regard) is a backward step; I'd prefer that the car had a dipstick to allow a visual inspection when cold. I don't think an electronic sensor is an improvement. Probably a whole other topic for discussion anyhow.

[MMMGuy]

Originally Posted by EarthboundMisfit

Well, we can agree to disagree on what we think the flaws in our cars are, but it seems that it is normal for the sensor to take so long to read oil level.

Digressing slightly, I think BMW's intent (in this regard) is a backward step; I'd prefer that the car had a dipstick to allow a visual inspection when cold. I don't think an electronic sensor is an improvement. Probably a whole other topic for discussion anyhow.

Ditto....bring back the stick..hate having to rely on more gadgetry for something as fundamentally simple as checking the oil level...

[DaveDee]

Originally Posted by Jin.ActiveMotorwerke

It is certainly not a flaw. It's more like precise engineering. You can probably say it's a bit too precise.

Oil density is dependant on oil temperature. And only at the right temperature can it measure the exact oil level it requires on M3/M5.

So the system is design to only read the oil level at oil temperature above 90 degree roughly. Nothing to do with the sensor it uses.

This might be so, but when doing an oil change it's not a good thing to have no physical check of measurement before driving off. Even with the correct amount of oil added it is still good to be able to check.
Mine takes up to 10 minutes driving to come up to operating temp before showing levels. The only upside is we know if there was something really wrong with the levels large warning alarms come up.
I have an oil pressure gauge also which adds a bit more confidence when starting up, but have to also have blind faith in BMWs warning systems