Strange problem with the Z4

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The car is 9 months old now and has just covered 14k miles. Over the past few days I have noticed a strange problem with the oil warning. After driving the car, when I turn the engine off, as I turn the key, the oil warning light comes on and flashes on the display "Add +1.0l". Any other time I'd put some oil in but when driving normally after a few minutes when the engine is up to operating temperature, the oil display is indicating that it is full. The only time it indicates as low is just as I turn the key to turn the engine off. It started this a few days ago and it does it every time now.

I don't want to add more oil in case it doesn't need it because too much oil can be worse than not enough. Any idea what the problem might be?

If only it had a dipstick life would be much easier!

Car is a 2008 BMW Z4 3.0Si Coupe.


PS, the dual mass flywheel is rattling again...and much worse this time. Oh joy, another week of X3 fun :mad:
 

I know nothing about cars so im just going off something i made up in my head! Could it be the fact its the cold weather? The cold decreasing the volume of the oil, then when its warm it expands the volume?

Flame me if im wrong, would be nice to know the truth :D

**edit - reread post properly, only does it when you turn it off... DOH**
 
I know nothing about cars so im just going off something i made up in my head! Could it be the fact its the cold weather? The cold decreasing the volume of the oil, then when its warm it expands the volume?

Flame me if im wrong, would be nice to know the truth :D

**edit - reread post properly, only does it when you turn it off... DOH**

It only does it when I turn the car off. At any time from turning the car on and whilst driving, the oil display indicates full. It's only when I turn the car off that it shows as being low. Another thing is when I turn it off and the display shows low, if I turn the car back on, it still shows the oil level as low, however, if I leave the engine running for a minute or two or take a drive, it goes back to showing as full. It's pretty confusing.
 
I have it booked into the dealers for a check up but I'd like to get some ideas before I let them loose on it.

TBH I'm becoming a bit fed up with the car. After a load of hassle getting the dual mass flywheel replaced a few months ago, after only a few thousand miles it is doing the same again only worse. The drivers seat is squeaking and creaking very loudly, the clutch slips sometimes when cold, the tyre pressure monitor takes random fits and now this problem with the oil sensor. The car is 9 months old FFS :(
 
Lots of electrics and sensors = Lots of stuff not to work properly. Does anyone really need a sensor to tell them when to pump their tyres up? I wouldnt trust one even if I had a car with it on.
 
Lots of electrics and sensors = Lots of stuff not to work properly. Does anyone really need a sensor to tell them when to pump their tyres up? I wouldnt trust one even if I had a car with it on.

I believe it's there as a legal requirement since the car has runflat tyres. If I had a slow puncture it would probably be undetectable without the sensors.
 
I believe it's there as a legal requirement since the car has runflat tyres. If I had a slow puncture it would probably be undetectable without the sensors.

Yup, I drove around for a week in the Prelude with a flat tyre due to the previous owner put runflats on it. Booked it in for a new wheel bearing due to the alloy/tyre becoming red hot, ended up with a new tyre. :D:rolleyes:
 
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You need to add 1.0l of oil. you have an oil pressure guage, when up to temp the pressure has increased and the low pressure warning is no longer triggered. People often make the mistake of thinking oil pressure warning lights in cars are oil level lights, in many cars your already at the point of potential damage when it is coming on.

Of course this could be all completely different with the z4 especially with the no dipstick issue.
 
Stick 100ml in and see if it stops doing it.

If yes, it needed oil, add another 900ml. If no, then something else is probably causing it.
 
You need to add 1.0l of oil. you have an oil pressure guage, when up to temp the pressure has increased and the low pressure warning is no longer triggered. People often make the mistake of thinking oil pressure warning lights in cars are oil level lights, in many cars your already at the point of potential damage when it is coming on.

Of course this could be all completely different with the z4 especially with the no dipstick issue.

I'm afraid of adding oil as the oil level display on the dash shows it as full at all times apart from when switching off. It's never at 3/4, 1/2 or 1/4 full, either completely full or completely empty. The oil pressure warning light is separate to the oil level display but it comes on the moment I turn the key to turn the engine off.
 
Cooper S used to have hissy fits if I went over a pot hole or something with RFT's. Had to reset it a lot.

BMW are only going to tell you to do what the display is telling you to do as they are brain dead at the best of times. I suggest going by what Biggles has posted.
 
It's asking for 1 litre, so add it. Your engine won't explode ;)

I was under the impression that too much oil can do more damage than not having enough. If the display shows the oil quantity as full at all times apart from when switching off, I'd be inclined to believe that there is plenty of oil in it. If there wasn't enough oil, surely it would show the level as being too low on the display at all times?
 
Stick 100ml in and see if it stops doing it.

If yes, it needed oil, add another 900ml. If no, then something else is probably causing it.

Sounds like a plan, but wouldn't it be better to add oil in 100ml increments?

Also maybe Z4's dipstick is somewhere else in the car? :p
 
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