Valve guides or Rings.

[popdemonic]

my AAN is now burning oil 2000kms/L.I know the manuals said as long as
the engine keeps it around 1000kms/L.It's just fine.Recently,I started to
notice some very lightly puff of bluish smoke when parking the car in the
sunlight so i tried to record the clips from behind to see how much the car
smoke out under acceleration.

here's some brief i have done on the AAN.
-compression test reveals 160+Psi on 5 pots.
-No visible blow by through out the dipstick.
-Big puff of bluish smoke burnt every morning.
-Spark plugs tips are all wet and gums(more or less# with motor
oil once removed.
-I bypassed the PCV and installed Mann Provent 200 oil separater.
-Replaced the valve stem seals 6months ago.Found some worns on the
guides when tried moving the valve tips left to right.
-visible boost leak through out the breather system.

I still have not removed the head yet since now I have 3 choices and still could not
make up my mind.
1.I have a rebuilt head laying.it needs 10X of intake valves.new headgasket kits.
2.rebuild this head#needs new guides,valve stem seals,regrinds valve seats.)
plus new headgasket kits.
3.I have a complete AAN full block with only 30,000miles on clock.I don't think i could ever find this low miles AAN on this day.

https://www.youtube.com/watch?v=kzc_iR_2HcY

[Zoig]

Smoke in the Video: My car did that when i had cracked rings and broken turbo. With rings only affected cylinder plugs had oil on them, also compression was lower then in other cylinders. Turbo smoked when the engine was warm and i had a lot of in front of the cooler, plugs showed oll burning only on cylinder 3 (because it's the best flowing one).

[popdemonic]

Hello Zoig,
i'm not that confidenced if that smoke were from the cracked rings.
I have had this smoke issue for almost 2 years.it's just getting worse.
my spark plugs are all gums with motor oil.driving this car under high boost.
the boost pressure will push out the motor oil through out the valve cover
gasket and spark plugs gasket too.i replaced a valve cover gasket kits for
a couple times until i found the excessive blow by caused this. my turbo is
gt2871 ball bearing.it's pretty hard to smoke out from the turbo since it required
much lesser oil feed into the CHRA than journal bearing turbo.recently i just
purchased the diesel gearbox,it might be a good time to pull the whole
engine and 5speed gearbox out and put all the new engine with diesel box in
though.Do i need to pop up the head and replace the new head gasket on
30,000miles engine or just keep it as is?

[prj]

You've posted about 10 threads about this already (okay, maybe not 10).
It is pretty clear from your description that you need an engine rebuild.

The 1l/1000km is stated only to cover their *****.
A well working I5 does not need topping up between oil changes.

The parts for a rebuild are between 500-1000 EUR (depends on how much the bores are out of spec and if you need pistons), very cheap comparing to newer engines.
If you have a second engine, even better, drop that in and rebuild the first one afterwards.

[popdemonic]

Hello Dmitri,
i've posted a couple threads but repost on this again since
the symptom is getting worse.i am not worried about the
expenses on rebuild but it's kinda stuck on my head
willing to know what is the culprit on the issue.if i decided
to put the new engine in,i still need to scratch on my
head to sort it out over again.

[prj]

Like all I5's before and after yours, it's the valve steam seals that are worn out and causing oil consumption.
Yours is not special. Exactly the same issue.

And if you're taking the head off do the bottom end too as the rings will be worn as well, especially if you get lots of blowby, they are worn for sure.