Oil level sensor issue.

[Derek MacKinnon]

Hi guys, been a long term browser and wanted to try and ask a question regarding my oil level sensor.

Basically the car has been sat for a couple years with not many miles each year, spent a lot of time doing a back end resto underneath the car.

Had it up and running a few months ago and noticed when going for an oil level reading that it wasnt reading.
Tried resetting it by holding down the BC button and you should get the spinning clock, I dont see that, I just get this symbol -.- and the idrive also says no measurement currently possible.

I purchased a new sensor directly from BMW, drained the oil and fitted that and after a good drive for 40 minutes im still not getting a reading.

Ive taken the plug off the sensor and checked all the wiring, it all seems good as far as i can see.

Just finished fitting a new thermostat so my plan is to warm the car up to temp, change the oil and filter again, im sure its 8.8L with a filter change, I just dont want to overfill, then drive it longer to see if it starts working.

Any ideas other than that?

I did download ISTA and have a D-Kan cable but ill need to watch some vidoes on how to use it if theres anything in there I can check.

[egebhardt]

I don't have a lot for you other than oil volume.

With a new oil filter and dry oil pan, I managed to get 9.8L into the engine. That's after removing the pan do replace the rod bearings.

Also, I understand 'progress' in terms of adding technology where it may not be needed but.... dam. I have to run the engine, potentially too low or too full of oil, for 20 minutes, just to know if it's too low or too full. I can't even check oil color. There should be a camera with light-bulb. Let's see how hard we can make it after 100 years of combustion engines.

[pjk380]

I recently replaced the oil sensor with a new BMW sensor. It registered pretty quickly, maybe within 15-20 minutes. My old sensor took forever to get a reading. If you know you have the correct amount of oil, I would drive it more over the next few days and see if it provides a reading. Sometimes it can take a few drive cycles to provide an accurate reading. Not sure why these oil level sensors are so inconsistent in getting and providing a reading.

[egebhardt]

20 minutes is about the fastest I can get a reading.

[spammysammich]

Originally Posted by pjk380

I recently replaced the oil sensor with a new BMW sensor. It registered pretty quickly, maybe within 15-20 minutes. My old sensor took forever to get a reading. If you know you have the correct amount of oil, I would drive it more over the next few days and see if it provides a reading. Sometimes it can take a few drive cycles to provide an accurate reading. Not sure why these oil level sensors are so inconsistent in getting and providing a reading.

Same, my old sensor took much longer to register even when fully warm than my new sensor.

[Scrippy]

Fastest readings are acquired with temperature reached, on a level surface and at idle (NOT MOVING). It will give readings on the go but they are mega delayed.

[Derek MacKinnon]

Years ago after oil changes I used to have it on idle for 20 minutes and would always get a reading.

I’ve tried the same here it’s just baffling. Not even available in idrive. Somethings going on. I don’t want to have to take it to BMW but I may have to at this rate.

[amrazM]

Does it say inactive on the idrive?

[Derek MacKinnon]

Originally Posted by amrazM

Does it say inactive on the idrive?

It says "oil measurement not currently possible"

Live I've mentioned you can do a hard reset on the BC button when you're in the oil level screen but I don't get the spinning clock I just get the symbol "-.-"

I do have photos somewhere ill post, I'm currently away from home on work for another week.

[tbone28]

Originally Posted by Derek MacKinnon

It says "oil measurement not currently possible"

Live I've mentioned you can do a hard reset on the BC button when you're in the oil level screen but I don't get the spinning clock I just get the symbol "-.-"

I do have photos somewhere ill post, I'm currently away from home on work for another week.

That's normal, part of the process. It starts off with that message before you get the spinning clock. It often takes a LONG time before I get a reading. I'll sometimes have to drive up to the next city before I get a reading.

[Derek MacKinnon]

View post on imgur.com

View post on imgur.com

Don’t know if these will work.

[Scrippy]

My oil sensor did this because I’ve changed the oil so much. It turns out there is not enough memory in the ecu for so many oil changes. I took my car to my local dealership and they had to recode me. Now my sensor only monitors level and does not prompt for mileage changes. I have 256.XXX and change oil every 5k. Prior to them coding me I had those dashes as well. If you haven’t done a lot of oil changes I would suspect wiring or a faulty sensor. I would unplug the sensor wire harness on both sides and do a continuity test on the wires. Outside of that pull codes from the car and see if you have any canbus breakdowns or open/short errors stored.

[Derek MacKinnon]

I’ve tried to follow the wiring back to the point I had the plenum out and all the wiring up
Trying to find the other end of it. I really need a diagram. Wiring isn’t my forte so I’ll keep digging.

I’ll get a proper code reader and see if there’s anything there.

I do have ISTA and a d can cable but I’ve only just downloaded it. Not sure how to get it connected to the car and reading codes yet. Think my cable may need an update as it came with a CD

[Derek MacKinnon]

Does anyone happen to know where the other end of the sensor plug wiring goes? I know roughly where it goes to but can find the cables or the plug that houses the other cables.

I did check for continuity as high up on the wires as I could down to the pin. I did notice two of them had continuity with each other but I’m unsure if it’s meant to be that way.

[pjk380]

Not sure if this helps.

[Derek MacKinnon]

Originally Posted by pjk380

Not sure if this helps.

Thanks for that.