[slimxb8]

Changed my oil Friday, 4 days ago. Put in my usual 7 quarts. Cluster said I still needed 1 quart. Add 1. Said I was half still low. Added one more. So if you're keeping up, I'm at 9 now.

So Sunday wife said oil light came on after driving 20 miles to church. She looked after being parked there for a while and saw nothing.

Didnt really drive Monday.
This morning it said I was 3/4 low. Coming home it was back it saying 1qt low.

I feel like it's a bad sensor... If I'm down 3qts or 1qt in a few days this thing would be hemorrhaging oil somewhere.

I'm at 147k miles on this 328i

Is my only option to drain and measure? I'm not adding 1qt because that'd be 10 if it's reading wrong.

[Groganrocket]

Mine says below minimum and when I shut it off and check it again later it’s fine, I wish they had put a dip stick! Think it’s a bad sensor.

[vncung]

Take a look ast this thread.
http://www.e90post.com/forums/showthread.php?t=926864
But yours hasn't reach 186k yet.

[slimxb8]

I remember that thread from a few years ago.

On way home I'm now down 1/4 at below the +1. At this point I guess I need to drain it and see how much there is. I still see no leaking or burning.

[ctuna]

Don't be tricked into adding to much oil due to the delayed
update of the oil sensing system . I won't believe what it says
till I have driven the car about three times for more than 20 minutes.
Also the length of the graph only measures the top quart.

Sounds like you need to measure by drainage at this point

[Efthreeoh]

I wish the Mods would make a sticky on how the e-dipstick actually works. It's been posted on the Forum at least 10 times by me alone.

The CBS will report the last level of oil it measured at the point the engine was turned off. So when an oil change is done and the correct amount of oil is added back into the engine, upon start up and immediate check of the e-dipstick one the time has passed (clock spinning) for it to provide a reading, it will report the last known measurement. So if your engine was a quart low when to did the oil change, the first reading you'll see, if you don't wait long enough, is the last level before the oil change.

The e-dipstick is not a direct-reading device; it doesn't instantly determine the new level of oil in the engine. It takes over 20 minutes and a good amount of driving to attain a new oil level. Basically the oil needs to be at operating temperature, the engine needs to run for over 10 minutes and the car needs to attain several parameters of acceleration and yaw (turning) until the oil level is accurately determined.

You've way over-filled the engine with oil. A friend of mine (and a very good mechanic BTW) blew out the front crank seal on his son's E90 by not understanding how the e-dipstick operates. He did the same thing you did.

[TomD335xicoupe]

That is a good post, I did not know how it works either. I usually do not check oil until about 2,000 miles after changing anyway but still good to know, thanks.

[robthewrench]

I would run it for an extended amount of time in your driveway. This will both allow time for the sensor to get another reading, and for you to look for any large discharge of oil or significant smoke.

If after this, and maybe some additional driving, you are still being told to add oil, I would go-ahead with a drain and measure. While this is a pain, it is still way cheaper than messing with the oil level sensor.

If the amount drained is easily over 7.5-8 quarts, I would say you have a bad sensor.

[Efthreeoh]

Originally Posted by robthewrench

I would run it for an extended amount of time in your driveway. This will both allow time for the sensor to get another reading, and for you to look for any large discharge of oil or significant smoke.

If after this, and maybe some additional driving, you are still being told to add oil, I would go-ahead with a drain and measure. While this is a pain, it is still way cheaper than messing with the oil level sensor.

If the amount drained is easily over 7.5-8 quarts, I would say you have a bad sensor.

All that anyone needs to do is drain the engine by opening the oil filter cap, oil filter cap, and remove the oil drain bolt. Let the oil drain until it drips. Change the filter, reinstall the drain bolt, and refill the engine with 6.9 (7) quarts, or 6.5 liters of oil. Then drive the car like normal. Check the oil level the next day if you want to see the full level on the e-dipstick.

Why people think all the oil doesn't drain out, or all 7 quarts doesn't go in, is a mystery. Where does everyone think the oil goes?

[robthewrench]

Originally Posted by Efthreeoh

All that anyone needs to do is drain the engine by opening the oil filter cap, oil filter cap, and remove the oil drain bolt. Let the oil drain until it drips. Change the filter, reinstall the drain bolt, and refill the engine with 6.9 (7) quarts, or 6.5 liters of oil. Then drive the car like normal. Check the oil level the next day if you want to see the full level on the e-dipstick.

Why people think all the oil doesn't drain out, or all 7 quarts doesn't go in, is a mystery. Where does everyone think the oil goes?

When I try to measure, I often wonder about how much I didn't get out of the filter, or don't get from the drain pan into the container I'm using to measure. I am probably over-estimating this loss at 1/2 quart or more.

[Efthreeoh]

Originally Posted by robthewrench

When I try to measure, I often wonder about how much I didn't get out of the filter, or don't get from the drain pan into the container I'm using to measure. I am probably over-estimating this loss at 1/2 quart or more.

I've never measured the residual in the OFH, I suck the oil out using a fluid extractor. But I think it's not more than 8 ounces. Keep in mind not every ounce of oil drains from the engine since a few ounces remains in the oil pump, and a few ounces sits it the head and VANOS system. What I was referring to is when the oil drain in the oil pan is opened, all of the oil drains out, less the residual amounts just discussed. It's not like only 6 quarts comes out, and the 7th is hiding from the drain hole.

My point about the fill is, you add 7 quarts to the fill hole in the valve cover, and unless you spill it, it all goes into the engine block. There is really no point in checking the oil level afterwards if the oil change procedure is properly followed.

[Desertraptor]

I'm having an issue with my sensor too. I hope.
Had the car a week. When I picked it up the gauge said full. Went for a drive on the weekend and the gauge said 1/4 down. It stayed at 1/4 down for a few days. Now today it says 1/2.
I can see some oil just behind the oil filter housing. But it's not much.
Today I booked it in for a look see.
I asked the mechanic how to know if it's a sensor or I am actually losing oil. He said the only way to know is drop the oil and measure what comes out. I can't get under my car to drop the oil.
But I read not to over fill the oil or it will cause damage.
I suggest you drop your oil instead of adding and adding.
The book says add a litre when the gauge is at min. I'll wait.

[slimxb8]

I am driving 30 min each way to work... And it's been a week now. Have today off and will drain it to ease my mind. Will post later what I found

[Efthreeoh]

Originally Posted by slimxb8

I am driving 30 min each way to work... And it's been a week now. Have today off and will drain it to ease my mind. Will post later what I found

vncung posted the link to my thread from 2012. Trust me I've been all through this issue with the oil level sensor with BMW dealership techs. It is very rare the oil level sensor give a false reading. It's a very simple device with really no electronics to fail. It's just a capacitor that uses an changing dielectric. I've finally figured out (keep in mind I've owned my car for almost 12 years and 330,000 miles) that you can't treat the e-dipstick like a direct-read mechanical dipstick; it just doesn't work the same. What does work well is when it tells you to add a quart, just add a quart and move one with life. The sensor has trouble codes associated with it, so if anything scan the car with a BMW scan tool and look for codes. It's no more difficult than that.