Z4 oil question. Needing help.

[stuart-ermrc]

Hi all, I hope this is in the right thread?

The car is a 2006 Z4 2.5si with 61,000 miles.

I’m currently in the middle of a tour of Europe. Just before we set off the car had an oil and filter change. Millers oil was used C3 5w30 (manufactures guidelines). After 1,000 miles the yellow oil light came on and asked for another litre of oil, I had 1 litre of Millers spare with me so I used that to top the car up. Then 700 miles later it asked for another litre. I stopped at a service station and bought ‘IP’ oil, though it was C4 5w30. I didn’t notice it was C4 and not C3 until after i topped up the engine. Anyway since the top up the engine seems a bit lumpy and it’s not idling very well in the 60 miles since. It also fully cut out once at a junction and the EML light came on. I don’t think this is linked to the C4? I’m in Florence Italy so a long way from home. Should I be worried about using 1 Litre of C4 mixed with 5.5 Litres of C3?

Once I’m home I’ll try and work out why it’s drinking so much oil, i had the ccv valve changed by BMW just before we set off as it was smoking a bit occasionally on start up & drinking oil at the same rate it is now.

Thanks,
Stuart

[Mave]

I suspect that the poor running is related to the oil consumption, rather than the oil spec.

[Mr.Jimbo]

I wouldn't worry about a litre of C4 in with the C3 but I'd be a bit worried as to why it's got such a drinking problem - far better to have a mix of C4/C3 in than no oil at all.

Have you had a look to check there is no obvious gross leak from the filter change or from the sump?

[blue_haddock]

stuart-ermrc said:

Once I’m home I’ll try and work out why it’s drinking so much oil, i had the ccv valve changed by BMW just before we set off as it was smoking a bit occasionally on start up & drinking oil at the same rate it is now.

I'd be looking at this sooner rather than later, last thing you want is the engine seizing at 100 + on an autobahn

[Wills2]

I'd get that to a local garage you can't tour Europe in a car drinking oil and running lumpy with the EML on go find a dealer and leave it with them and go off for the day.

Edited by Wills2 on Friday 17th September 12:11

[thecremeegg]

Common oil leak areas on a Z4 (other than the CCV) are the oil filter housing and the cam cover gasket. The latter only usually weeps a bit so it's unlikley to be that.
Check the oil filter housing as mine had a leak and was drinking oil quite quickly

[Bennet]

I hate our Z4. It looks good, and the roof comes down, but it's uncomfy, nothing special to drive and there is constantly something wrong with it. Usually more than one thing. And yes, ours also drinks oil.

[Tomm3]

Bennet said:

I hate our Z4. It looks good, and the roof comes down, but it's uncomfy, nothing special to drive and there is constantly something wrong with it. Usually more than one thing. And yes, ours also drinks oil.

Ouch!! Agree they look great but not the rest. Plenty special to drive, 3 litre straight 6 round to 7000 and handles on rails. Mine not using any oil touch wood and tbf not the sheer fun of a Boxster but after over a year with it I still love getting in.

[Bennet]

Tomm3 said:

Plenty special to drive, 3 litre straight 6 round to 7000 and handles on rails.

The 3.0 might well make it special. I can't argue about the engine. Ours (it's actually my wife's) is only the 2.0, but I honestly don't mind the power (or lack of.)

Without looking for a protracted debate on this, I think if you value speed, grip and stopping power, it's probably a great car. It's very easy to drive it very fast.

If you're looking for steering feel, engagement, involvement, and things of that ilk it's maybe not so great.

Or maybe you personally find it very involving. It's all relative and it really, really depends on what you're comparing it to. I drive it back to back with my 1987 MR2 which is objectively worse in every metric, but offers significantly more feel and engagement through every single control. The MR2 feels like a sports car, where the Z4 just feels like a car.

I wish you the joy of the thing and this is just my opinion. I'm not trying to dump over anyone's pride and joy.

Edited by Bennet on Friday 17th September 13:24

[g3org3y]

Mave said:

I suspect that the poor running is related to the oil consumption, rather than the oil spec.

Agreed.

I think 1L/1000 miles is considered within tolerance but the OP's description sounds like there's definitely an issue.

blue_haddock said:

I'd be looking at this sooner rather than later, last thing you want is the engine seizing at 100 + on an autobahn

Agreed

Could it be that whoever did the oil change accidentally threw away oil filter housing cap insert?


Missing that can definitely causing some idling/running issues.

Edited by g3org3y on Friday 17th September 15:28

[stuart-ermrc]

Hi all, thanks for the replies. The car has been running perfectly since (and before) the oil change. The ccv valve and the oil change was roughly 1,600ish miles ago. Just the past 60 miles its started to run rough and coincidentally just after i topped up the oil. I did have a tiny bit of spillage with the oil, less than 50ml when i started to pour I missed the hole. I did dab it up as with a paper towel but it was only the plastic cover I could access and some of the oil will have seeped through to the engine bay. But there wasn’t any white smoke or funny smells when i drove the next 60 miles. Unless some of that oil might have gone on something electrical? Fun times.

[stevieturbo]

Wills2 said:

I'd get that to a local garage you can't tour Europe in a car drinking oil and running lumpy with the EML on go find a dealer and leave it with them and go off for the day.

Edited by Wills2 on Friday 17th September 12:11

I'd be joining a recovery service with a good EU cover !! lol and hope it survives any lead in time

[stuart-ermrc]

Got it booked in on Monday at a garage. I’ve a very good breakdown and recovery back to the UK worst case…

[g3org3y]

FWIW, I don't think mixing C3 and C4 oil would have caused any adverse issues. A code reader would be very helpful! Could be a Vanos solenoid.

[Krikkit]

How did you get on OP? Hope it wasn't too disastrous.

[stuart-ermrc]

Krikkit said:

How did you get on OP? Hope it wasn't too disastrous.

When I started it up on Saturday there was no oil loss or smoke or anything. The car ran fine. I’ve since done a further 750ish miles and nothing really to report.

Randomly this morning on startup there was a small bit of blue smoke and a lot of white smoke for around 30 seconds. But yesterday we left 30 degree heat and woke up today in 10 degrees so i’m 99% sure the white smoke was condensation. The car was covered in condensation and it was parked in the shade this morning.

We are in Switzerland just now and have a further 1,000+ miles until we are home in Glasgow on Sunday evening. Fingers crossed!