[cole1179]

I have a 2006 330XI and it’s always burnt oil for as long as I’ve had it. Also replaced the valve cover gasket ~50k miles ago. I’ve needed to put a quart of oil in it every 800-1000 miles which seems to be pretty standard. However, recently I got the oil level below minimum warning while driving, which had never happened before. I was almost home so i just got home, parked it, put in a quart of oil. Next day, it was immediately below minimum again after maybe 5 mins of driving. I pulled over and put ~3/4 quart in. Went to drive it again a couple hours later and its below minimum AGAIN. There’s no puddles where I’ve been parking, no smoke, and no leaks that I can see anywhere. And to lose that much in such a short time, I’d imagine a leak would be obvious.

Any idea what the problem could be? Perhaps a faulty sensor?

Also, I typically do work on the car myself but I’m a few states away at college right now without a good toolset or anything. If I continue driving it as is, do you think I’d get a low oil pressure warning before damage to the engine is done? (assuming it actually is losing oil that fast)

Any advice is much appreciated. Thanks!

[sabino56]

I’ve a 2006 330i and have been wondering similarly if oil sensor is going bad or losing oil. I had traditional oil pan leak for a long time and would be occasionally adding oil, I assumed due to leaks. Replaced opg and after a bit got a low oil warning - not sure how long, wasn’t paying attention. I added a qt and a checked and it showed full. A few days later check and it showed 1\2. I didn’t add more oil as worried about overfilling. Now, I will check oil level after driving in garage and it will be varying between 1/2 low and 3/4 low from time to time. Now it’s bouncing between low oil indication and 1/4 low. I’ve read in posts that the oil sensor can’t really fail but perhaps the connectors are getting corroded. I’m thinking I may replace it regardless just to check it off, change oil and starting paying attention to how much oil I’m adding and at what mileage.
Sorry I can’t help - looking for similar advice.

[Gemini562]

It sounds like a faulty oil level sensor issue, especially if there are no visible leaks or smoke and oil seems to disappear too fast, get the sensor and oil system checked asap

[crashoverride]

Are you seeing any oil in your coolant..??? Happens more often than it should.

I have a weird thing were if I go around a tight corner usually a parking spot or such my car will die. But rare and I've started to notice when I need to add oil. I'm thinking there is some sort of low oil protection. But alas who knows.

[cole1179]

Originally Posted by sabino56

I’ve a 2006 330i and have been wondering similarly if oil sensor is going bad or losing oil. I had traditional oil pan leak for a long time and would be occasionally adding oil, I assumed due to leaks. Replaced opg and after a bit got a low oil warning - not sure how long, wasn’t paying attention. I added a qt and a checked and it showed full. A few days later check and it showed 1\2. I didn’t add more oil as worried about overfilling. Now, I will check oil level after driving in garage and it will be varying between 1/2 low and 3/4 low from time to time. Now it’s bouncing between low oil indication and 1/4 low. I’ve read in posts that the oil sensor can’t really fail but perhaps the connectors are getting corroded. I’m thinking I may replace it regardless just to check it off, change oil and starting paying attention to how much oil I’m adding and at what mileage.
Sorry I can’t help - looking for similar advice.

You may be in the same boat as me here, but one piece of advice that I’ve gathered from reading different posts, is that you shouldn’t put more oil in until it tells you to. Like if it’s half way to max, leave it until it gets to the last bar. Not sure why, maybe there was an explanation but I saw quite a few people saying this.

[sabino56]

Thanks, yeah - I’ve read same that overfilling can be a dangerous. I’ve not added anything except when it indicated to add +1qt. When it went from full to 1/2 down the next day I worried I could have potentially overfilled if the sensor was erratic and haven’t added anything since. I feel better now in the sense that the sensor indication has on average gone down.

crashoverride thanks for suggestion. I checked coolant level and ofg area and everything appears ok.

I’m thinking once it warms up a bit I’ll clean the contacts on the sensor and see if it does anything out of curiosity - and if no, just change the sensor and track more carefully mileage vs oil usage going forward. I miss the dipstick.

[Efthreeoh]

https://www.e90post.com/forums/showthread.php?t=1533444

[sabino56]

Originally Posted by Efthreeoh

https://www.e90post.com/forums/showthread.php?t=1533444

Great post, thanks!
I was aware that engine had to reach a certain temp to measure oil level but didn’t know it checked for motion also. So if one started the engine and let it idle until it came up to temp and checked the oil level would that be the “static” measurement as it hadn’t gone thru the driving accel stuff?

In my case, I usually check the oil at the around the same place on road from my house where it’s level and it’s reached the temp (and, now I know some movement) to do so. After adding 1qt when it had indicated to do so with warning light, the sensor read full and I was happy (other than wondering why I was still losing oil after replacing the opg…). A day or two later when I checked the sensor said 1/2 below full and stayed there. That bothered me but I didn’t add any more oil. Overtime it’s gone to 1/4 and sometimes will flash add +1qt. I don’t have concern with +/- 1/4 as I assume that’s the resolution of the sensor output. I have to think the sensor or connector or something is not right when it jumped from full to 1/2 overnight?
That is without anything obvious going on with oiling system, increase in coolant level, puddles under car, smoking, etc.

Regardless when I change the sensor I’ll post if I find anything interesting.
OP, my apologies for hijacking your thread.