Z4-forum.com

My 2005 2.2 was being used for my commute to Heathrow to South Wales couple of times a week, if I filled the oil to the max mark within 500 miles it was at the min mark and then the oil light would flash on turning off
She's laid up in my garage for winter now and want to get to the bottom of this, compression test shows 180 on all six cylinders, I left her for about a month without starting in case the valve guides are leaking to see if I got a massive smoke belch on startup but nothing
I've changed all the PCV system. I can't see any leaks anywhere so where do I go from here, plugs are clean, well mostly number 2 had a slightly rich colour compared to the others but hardly 3 litres in 500 miles worth

Any help much appreciated

Are you sure the ccv return path via the dipstick is clear? What suction do you feel opening the filler with the engine running?
Rob

CCV has all been replaced, there's not a huge auction but the engine note changes

Wafoo wrote: ↑Thu Dec 07, 2017 5:01 pm CCV has all been replaced, there's not a huge auction but the engine note changes

The ccv return via the dipstick can become blocked, it may have been overlooked while changing the rest of it.
You could discount the breather by plumbing in a catch can & seeing if it fills with oil, that oil would otherwise be burnt by the engine.
Rob

OP can you smell burning oil at any time ? Check your cam cover gasket and oil filter housing gasket for leaks. I replaced all my CCV system a few months ago and discovered whilst doing so that the above two were leaking like sieves ! Hardly used a drop of oil since

It will probably be the rings stuck

Compression check only shows that the compression ring is fine, the oil control rings will probably be gummed up and stuck in the piston lands

Z4M-2006 wrote: ↑Thu Dec 07, 2017 11:22 pm It will probably be the rings stuck

Compression check only shows that the compression ring is fine, the oil control rings will probably be gummed up and stuck in the piston lands

It’s a bit of a chicken & egg thing, the rings can get gummed up by an ineffectual breather system-the engine then consumes even more engine oil......
Rob

Interesting problem. Using oil at this rate I would have expected considerable smoke, rough running and oiled plugs so before worrying about ring problems I would make sure it is not CCV related or simply an oil leak. I am sure others will correct me but the oil control ring sits beneath the compression ring so if compression is normal it is unlikely any oil will pass this ring into the compression chamber.
Is this a very high mileage car which has not been serviced regularly.

Mike6 wrote: ↑Sun Dec 10, 2017 7:21 pm Interesting problem. Using oil at this rate I would have expected considerable smoke, rough running and oiled plugs so before worrying about ring problems I would make sure it is not CCV related or simply an oil leak. I am sure others will correct me but the oil control ring sits beneath the compression ring so if compression is normal it is unlikely any oil will pass this ring into the compression chamber.
Is this a very high mileage car which has not been serviced regularly.

Oil burners don’t always seem to smoke mike, the cat & reverse flow silencers full of sound absorbing wadding filter out most of the smoke
Rob

Hi guys .
I had an e46 2.2 that always used oil about a ltr every 500 miles or so my car never smoked or burnt oil , lots of info about this on their forum as it seems very common and some guys went above and beyond to fix this and never quite cured it ! not sure but think its the same engine .
If it is there are lots of info about this problem on e46 forum and what some of them did to solve it
Hope this helps .

Greg 01 wrote: ↑Sun Dec 10, 2017 9:45 pm Hi guys .
I had an e46 2.2 that always used oil about a ltr every 500 miles or so my car never smoked or burnt oil , lots of info about this on their forum as it seems very common and some guys went above and beyond to fix this and never quite cured it ! not sure but think its the same engine .
If it is there are lots of info about this problem on e46 forum and what some of them did to solve it
Hope this helps .

Hi, if its needing oil at that rate & not leaking then it’s got to be burning it
Rob

Hi Rob.
I had the car 4 years it used the oil right from getting the car .
I thought I had been ripped off till I started to research it on the forums .
The emissions where always spot on and was never smelly also no burst of smoke from cold etc I just lived with it and bought cheap oil , over the time I had the car it never got worse and never got better . This is how I found out about the oil !
Bought the car and picked it up Manchester drove strait to Scotland to see madonna with my wife .
After concert driving home n the oil light came on stopped at a garage bought some oil and set off .
Oops I forgot to shut the bonnet properly. Yes it came up n over the car and trashed the bonnet and screen .
The garage i bought it from Nissan Manchester fixed all the damage for free but never got to the bottom of the loss of oil .

Our R56 Mini goes through oil at an alarming rate on motorways. Fine on short journeys almost no oil used but will easily start going through it on motorways. It could be on the M4 you are in the outside lane gunning the car, 90 mph between Swindon and Reading which is the norm, which I think will cause the car to drink oil. Modern synthetic oils are very thin so perhaps a slightly thicker viscosity or just buy a 5 litre can from Eurocarparts and keep it in the boot with a funnel. Our girls seem to have a drinking habit !

Thanks for the info everyone
She is a high mileage 140000 but has a good service history
I was thinking if she was burning it wouldn't the plugs be oiled up, they're all ok except for the one which is slightly dark but not gopping
If the oil control rings are gummed up is that an engine out job?
The mileage she does now ( less than 4k a year), I could probably live with it but emissions on MOT might be problematical

Wafoo wrote: ↑Mon Dec 11, 2017 4:22 pm Thanks for the info everyone
She is a high mileage 140000 but has a good service history
I was thinking if she was burning it wouldn't the plugs be oiled up, they're all ok except for the one which is slightly dark but not gopping
If the oil control rings are gummed up is that an engine out job?
The mileage she does now ( less than 4k a year), I could probably live with it but emissions on MOT might be problematical

The plugs will cope with a certain amount of oil burning before they foul up depending on the grade of the plug and the type of journey driven.
If the sumps removed, the big end can be removed & the piston removed from the top after removing the head
Rob