Strange problem with the Z4

mr tommo · 27 Nov 2008 at 09:13

Dandle said:
Thats because a new engine was was brought out in 2005 or 2006 with a magnesium/ally crank case it has very little in common with the older 3.0 il6.

Ahh was going to say, mine has one but its a 2003 Z4.

Ive noticed after a more spirited drive, the yellow oil light comes on when I turn the engine off too. Yet driving around normally, it doesn't.

Checked in the manual and it means it needs topping up within the next 50 miles IIRC. Checked the level with the dip stick and its smack bang in the middle of the 2 marks. :confused:

[TW]Fox · 27 Nov 2008 at 09:20

Ours does this as well. It's not supposed to, so I am arguing with BMW to get the sensor replaced at the moment. The 530 doesnt do it.

mejinks · 27 Nov 2008 at 09:41

[TW]Fox;12975830 said:
Have you checked the level? If its fine and the light isn't red its a faulty oil sensor. But i agree, don't buy another one, after all a failed sensor on a 10 year old 2 and a half grand 5 Series is unacceptable.

My sarcastic wit is lost again :rolleyes:

I was actually waiting for the jap crew to come along and say about how unreliable BMWs are....

mr tommo · 27 Nov 2008 at 09:50

[TW]Fox;12977007 said:
Ours does this as well. It's not supposed to, so I am arguing with BMW to get the sensor replaced at the moment. The 530 doesnt do it.

Is yours still under warranty? Does it only happen after a spirited drive too?

Let me know how you get on.

thepharcyde · 27 Nov 2008 at 10:12

[TW]Fox;12976959 said:
The E39 is a 5 Series.

Well done clueso

mejinks · 27 Nov 2008 at 10:21

thepharcyde said:
Well done clueso

Actually, you are both correct.

I have an E39 and an E36

Giddy · 27 Nov 2008 at 10:52

I've had this in the past, turn the engine off and the oil light comes on, usually just before a service is due. Just top it up a little.

audiolab · 27 Nov 2008 at 12:35

I am at 8 months old and just over 5000 miles on my Z4. So far not a problem, it is a bit wierd not having any manual method of checking the oil. The book just says that the car should be run for at least 5-6 miles and be warm, then you press the botton on the dash and it checks it. When you try this does it say you need oil?

Sorry to hear your woes, I had a similar experience with my las E46 and in the end this drove me to dark side (Audi) for a few years. Just don't let up on the dealer.

[TW]Fox · 27 Nov 2008 at 12:41

mr tommo said:
Is yours still under warranty? Does it only happen after a spirited drive too?

Let me know how you get on.

Yea we have AUC warranty. It comes on after most drives. I'm convinced its a faulty level sensor, the dealer disagrees. I'm actually more concerned that the guy in the workshop checked the level and decided it was empty - imagine what would have happened had I authorised them to top up with a litre!?

Scuzi · 27 Nov 2008 at 12:42

audiolab said:
The book just says that the car should be run for at least 5-6 miles and be warm, then you press the botton on the dash and it checks it. When you try this does it say you need oil?

When I do that the gauge shows the oil as being completely full. It's only the second I turn the key in the ignition that it displays as low.

I'm going to put in a few hundred ml to see if that makes a difference.

mr tommo · 27 Nov 2008 at 13:15

[TW]Fox;12978118 said:
Yea we have AUC warranty. It comes on after most drives. I'm convinced its a faulty level sensor, the dealer disagrees. I'm actually more concerned that the guy in the workshop checked the level and decided it was empty - imagine what would have happened had I authorised them to top up with a litre!?

To be fair he's probably just confused by the most ridiculous dipstick design in the world on the Z4!

Im going to get mine as close to max as possible. Is it 5 mins after a drive for checking oil level? And is the level instantly altered as soon as its put in or does it have to drain through or summat? Clueless at stuff like this.

[TW]Fox · 27 Nov 2008 at 13:19

Checking the oil is ridiculous but a BMW tech should know how to do it. You need to check the oil with the car parked on level ground, 5 minutes after switching the engine off with the car at full operating temperature. A reading taken at any other time will be inaccurate.

--ki-- · 27 Nov 2008 at 13:59

Mine kept coming on under the same conditions also, but since it was 1k approx to service I just had them do a service, hasn't happened since. Since yours (Scuzi) has the same milage as mine, may be worth getting a service. It was atleast good to get other faults diagnosed steering column failure, secondary key failure and some elements in rear windscreen burnt out (all sorted under warranty)

Scuzi · 27 Nov 2008 at 14:41

--ki-- said:
Mine kept coming on under the same conditions also, but since it was 1k approx to service I just had them do a service, hasn't happened since. Since yours (Scuzi) has the same milage as mine, may be worth getting a service. It was atleast good to get other faults diagnosed steering column failure, secondary key failure and some elements in rear windscreen burnt out (all sorted under warranty)

I notice you mention steering column failure. How did this materialise? I have noticed that when cornering hard, there is quite a pronounced "click" and a knock from the steering column which can be felt through the wheel. It has only started doing this recently.

Can I add a failed steering column to the list now too?

Regarding the oil, I put in 300ml of Castrol Edge and took it for a spin. The light did the exact same thing. I put the rest of the bottle in (1l in total) and the problem seems to be fixed.

Lesson learnt - The electronic oil gauge is completely unreliable. You'd get a more accurate reading by telephoning your local vicar and asking him.

[TW]Fox · 27 Nov 2008 at 14:42

Don't phone him on Sundays whatever you do.

--ki-- · 27 Nov 2008 at 14:58

Scuzi said:
I notice you mention steering column failure. How did this materialise? I have noticed that when cornering hard, there is quite a pronounced "click" and a knock from the steering column which can be felt through the wheel. It has only started doing this recently.

Can I add a failed steering column to the list now too?

Regarding the oil, I put in 300ml of Castrol Edge and took it for a spin. The light did the exact same thing. I put the rest of the bottle in (1l in total) and the problem seems to be fixed.

Lesson learnt - The electronic oil gauge is completely unreliable. You'd get a more accurate reading by telephoning your local vicar and asking him.

Mine manifests itself on most start-up the power steering failure light would come on and all power assistance was gone, was solved by cycling the engine but was told its a steering column failure this is being order and fixed next week along with the other broken bits.

But as said before after service the light never came on again ('mind its only been 3 days).

Scuzi · 27 Nov 2008 at 16:12

Ahh right, fingers crossed then. Thanks.

The car is booked in for a check up next Thursday so we'll see how that goes. I'm also booked in to have a look at the 335i and M3 when I drop mine off. Just looking of course.....

Simon · 27 Nov 2008 at 16:24

You sure its not a oil level sensor when off and then turns into a oil pressure sensor when the engine is running?

There is no way a oil level sensor can give an idea of oil level when the engine is running.

Dangerous Dave · 27 Nov 2008 at 16:32

Simon said:
You sure its not a oil level sensor when off and then turns into a oil pressure sensor when the engine is running?

There is no way a oil level sensor can give an idea of oil level when the engine is running.

Using vagcom on my Golf the sensor tells you in centimetres how much oil is in the sump and still shows this when the engine is running. You can also display the level at which point the low level light comes on this appears to vary with oil temperature. Not got a clue if it is accurate though.

Scuzi · 27 Nov 2008 at 17:32

Simon said:
You sure its not a oil level sensor when off and then turns into a oil pressure sensor when the engine is running?

There is no way a oil level sensor can give an idea of oil level when the engine is running.

According to the manual, it indicates the level of the oil. There is an oil pressure warning light which is separate. Since there is no other way to check the oil level, I assume BMW have figured out a way to measure oil quantity whilst the engine is running although I have my doubts about it's accuracy.

The engine has to be running for it to display anything, it doesn't work with the engine off.