2006 Z4 2L burning a lot of oil

[herbialfa]

I've been in ownership of this "great" car for albeit 6 weeks. Pulls like a train but leaves a blue cloudy mist behind it when its warm

I've had the oil (4.5L) and filter changed 4 weeks ago and the oil light has come on then the engine management system light is now on.

I've taken it to my local garage who do repairs and they have said its "burning oild like a good un and might be a rebuild".

Now the only thing that alerts me to this problem is the cloud of blue smoke, everything else works/ goes at it should.

Any suggestions/ ideas???

TIA

[helix402]

It’ll be faulty valve stem oil seals.

[herbialfa]

Thank you for your input is this a costly job? If so ball park? Your advice is much appreciated

[herbialfa]

Can you elaborate please?

[helix402]

The valve stem oil seals harden with age and allow oil to enter the combustion chamber and leave the engine as blue smoke.

Afraid I don’t have any idea of the cost to replace them. It’s a common problem on the BMW N46 engine. Which was made near Birmingham.

[herbialfa]

Many thanks for your input!

[iSore]

These things also have piston ring issues.The N46 runs hotter than even the N42 did before it, which is why they piss oil out - the seals and gaskets are literally baked to a crisp. You could try lifting the inlet manifold off and fitting a new breather, but a smokey 2.0 BMW engine is par for the course. TADTS.

Too late now, but never buy the 2.0 Z4 - six cylinder only.

[herbialfa]

Thanks for your input. :-)

Its now at an Indy garage where funnily enough they had a 2L 03 plate in with the same issue and the guy reckons its the crank case vent pipe which is blocked. Apparently this is a common issue.

Now booked in for next Thursday so we will wait and see. No loss of oil when its sitting on the drive for the next 6 days as it only burns oil when driving.

[helix402]

I think it’s unlikely to be the crankcase breathing system on that engine causing the problem.

[herbialfa]

Hi Helix thanks. So what would be your thoughts?

[herbialfa]

& WHAT DOES TADTS stand for?

[helix402]

The most common cause of high oil consumption in these engines is valve stem oil seals. As isore mentions he has experience of worn piston rings too.

I once looked at an E90 320i with a smoking problem, it had already had the crankcase breather and pipes changed to no avail. The owner decided to live with the problem due to cost of fixing it in relation to the value of the car.

[iSore]

herbialfa said:

& WHAT DOES TADTS stand for?

"They all do that Sir".

[herbialfa]

Well I had the CCV changed for a cost of £93 all in and the problem has gone!

No smoke, no lights! Well chuffed!

[helix402]

Excellent result!