B7 2.0 TFSI Piston ring replacement

[Charlie Farley]

And a very good afternoon chaps, hope you're all dealing with the xmas surplus's ..turkey being one..lol
Anyway less of the turkey talk, I may be in a piston ring replacement situation but before I make further steps I was hoping to get a better idea on what options are open to me as a DIY job of said task.

I posted a thread in general automotive re compression test kits so hopefully i'll get some good feedback on that front , but , is there really a preferred route to go down with ring replacement on a DIY basis.

I really cant be throwing shed loads of cash at a garage doing it when I can do it myself but as with most things , there is the easy way or the hard way, i'd prefer the easy DIY route really.
So any thoughts or suggestions on the way forward on this fix for my B7 2.0tfsi lump
rob

 

[i3oricua]

That seems like a pretty big task Rob. I haven't done it myself so I may be speaking out of turn. My spare block should be done soon but I bring that up to say that to get to the piston rings you'll have to at a minimum, drop the oil pan so you can disconnect the pistons from the crank. You will probably have to remove the head as well unless you drop the crank and everything from the bottom. That's something I wouldn't recommend because you could scratch the walls of the bores on removal and installation of the pistons. It sounds crazy, but it would be easier to remove the engine to do the work.

 

[Charlie Farley]

Thanks for the reply Edgar, it's not really something I was looking to do but recently my oil consumption has increased a fair bit , even making allowance for the catch can retaining oil etc its still using more.

Recently I've noticed some puffs of smoke when overtaking and there is most certainly more soot on the tailpipes and tailgate.
The soot alone could be attributed to fuelling and Lambda issues but VCDS is showing no probs with those sensors, so logic tells me possibly rings worn or sticking ring/rings hence why i'm looking at compression testing.

From a performance standpoint , the car flies and is going on top form which kinda questions low compression but if rings are worn or sticking that would tend to swing towards the increased oil consumption as its not leaking anywhere else now, so sitting on the fence at the moment...

I was thinking from below to start with but I don't have a lift , engine out seems a better plan as I would get the chance to do the clutch / DMF and decoke the head properly of the car, then new valve seals etc, any other bits while its all out.

Maybe its one of those jobs that will indirectly help rectify a whole raft of other issues that need addressing sooner than later, not that i'm looking to make work for myself but just concerned on the oil consumption issue and where it may lead if not dealt with.

rob

 

[DieselJake]

Thought all VAG 2.0t's had a habit of drinking oil, you said oil was leaking from the valve cover Yesterday not that the car was just being thirsty.

Could always take the car to a proper mechanic for a second opinion and this compression test...

 

[GDCAUDIA4B7]

Just drop the engine, if you have the clutch/flywheel to do it makes sense

 

[Beardymat]

Its a head off and sump off job to do rings Rob as you have to compress the rings to get the piston to slide into the cylinder and the ring compressors are designed to work from the top, besides which you would also need to remove the crank to get them out of the bottom.

Just another thought before you go down this drastic route but have you considered you may be losing oil through the turbo? This would account for some of the oil in your intercoolers and also the smoking you're getting. Its normal to get a little oil past the seals in your turbo and this only gets worse with age. Have you checked your intercoolers since doing the PCV mod?

 

[GDCAUDIA4B7]

https://www.halfords.com/workshop-tools/tools/hand-tools/laser-compression-tester
this should be ok mate

 

[Charlie Farley]

Thought all VAG 2.0t's had a habit of drinking oil, you said oil was leaking from the valve cover Yesterday not that the car was just being thirsty.

Could always take the car to a proper mechanic for a second opinion and this compression test...

Not all drink oil, some are worse than others really, just down to pot luck I think.
The valve cover leak appears to have been a one off and stemmed from the oil filler cap not seating fully and oil being blown out around the side , nice and dry in that dept now.
Externally there are no oil leaks so the loss cannot be accounted for as leaks, so the increase in consumption must be internal , either getting past the rings or down leaking valve stem seals.

 

[Charlie Farley]

Its a head off and sump off job to do rings Rob as you have to compress the rings to get the piston to slide into the cylinder and the ring compressors are designed to work from the top, besides which you would also need to remove the crank to get them out of the bottom.

Just another thought before you go down this drastic route but have you considered you may be losing oil through the turbo? This would account for some of the oil in your intercoolers and also the smoking you're getting. Its normal to get a little oil past the seals in your turbo and this only gets worse with age. Have you checked your intercoolers since doing the PCV mod?

IC's are nice and clean , turbo is not that old as it was replaced by audi at approx 36k miles , well had a new short motor fitted aswell by audi just before that.
Since fitting the PCV mod the turbo's been nice and clean .
In theory the milage the motor has covered and the turbo would suggest the rings are not to blame , no way that they would have worn that much at 40k miles, but oil's going somewhere.
I have done a bit more research and it would appear the oil consumption issue with the 2.0tfsi in the B7 does vary wildly from car to car , but the BUL engine does appear to suffer more , maybe the higher compression ratio in the BUL makes it worse when the rings start to wear .

The head does need a serious decoke , I know that for a fact , and the clutch will need doing sooner than later, it's not slipping etc but at 72k its probably more worn than not .

I have run vcds and done some data logging and all seems normal , no error etc and O2 sensors don't appear to be playing up, strange as the car does go really well but just uses a lot more oil than it normally does , and its a fair bit more over a monthly period.
I know the sports cat can allow more soot to get pass the core but i'm getting a lot , and if it's not fuel related and the car goes well then what else can it be really.
Oil being burnt in the combustion process .

maybe just time to rip out the lump and get all the work done in one swoop, in the long term it will save me a fair bit I suppose.

 

[Charlie Farley]

In a way it throws up another possible route to take.
I had shelved any further engine power mods on the original BUL engine but maybe more sensible now to pickup another donor engine and spend the money on getting that upto a semi decent spec .
keep the original lump safe for future use etc, a few things to ponder over …

cheers
rob

 

[Baka]

It might be worth investigating the amount of pressure in your crankcase.

Excessive crankcase pressure can cause seals to fail and increase oil consumption, as it's literally trying to force oil out any hole it can find.

 

[Charlie Farley]

It's possible but with the pcv delete setup i'm using the cranckcase etc is getting vented very efficiently now but I see what you're saying chap.
I did have a dreaded brake vacuum pump oil leak last month but sorted that and its all be super dry around that area since.
Maybe worth me doing the comp test to compare each cylinder , i'm going to do a full oil & filter change next week then do a milage based consumption test to see how many miles i'm getting per 0.5 ltr of oil now.

thanks for the suggestion Baka....all input is greatfully received.

rob

 

[Charlie Farley]

I 've pulled all four spark plugs and they look normal not sooty or oily, the only item I haven't been too sure about still is the MAF , possibly its still not working properly after it was cleaned, but surely if there was an overly rich mixture the plugs would indicate the same.

 

[Baka]

No worries mate. It's something that'd be worth ruling out, as it can cause the symptoms you're having. Especially if the boost pressure in the inlet manifold can find its way into the crankcase.

 

[Sygh2k]

Valve guides and seals maybe?

 

[AlexMac]

Any chance your normal driving routine has changed Rob? Notice that my oil consumption always rises at this time of year. Shorter and more frequent journeys (often on a cold engine) means I'm having to top up once a month, whereas over the summer (travelling longer distances more frequently) I can go 2 or 3 months at a time without needing to add a drop.

 

[Charlie Farley]

Its got me scatching my head now

Any chance your normal driving routine has changed Rob? Notice that my oil consumption always rises at this time of year. Shorter and more frequent journeys (often on a cold engine) means I'm having to top up once a month, whereas over the summer (travelling longer distances more frequently) I can go 2 or 3 months at a time without needing to add a drop.

Its got me baffled really as the normal suspects for the problem don't appear to be a problem....
been out for a good blast this morning and the car really does perform outstandingly well , if there is a compression loss it is not showing itself from a performance standpoint.
Also tried to get it to puff out again and it wont, so I just don't know really.

I spent a good few miles driving in a lower gear to keep the rpm's over 3k , (got through some petrol) to try and burn off any excess carbon etc , that may have helped , anyway I think it's something I need to monitor for a good 500 miles or so and see what happens from that.
Whatever the outcome the head is going to get a full decoke and new seals, and go from that.

cheers
rob

 

[fonz600]

How smokey is it on tickover?

Mine used to give wee puffs if I quickly pulled out onto a roundabout or accelerated coming off one.
I did a PCV delete recently and now my car smokes quite a lot on idle. May be a coincidence though???
I have a decat so expect a little more bit that’s been fitted for years now.
I’m concerned my fuelling may be running lean due to the decat or the there is a drop in oil pressure(oil pickup hasn’t been changed) as that caused the car to run really bad when an oil filter had gone bad when I pr3viously had the car in storage.
I have VCDS but can you even log A/F and oil pressure?
Just my thoughts on my own car in case it’s not crossed your mind.

 

[antwan64og]

Does it smoke on idle or when you take off from a stop?
I’d lean more towards worn stem seals/guides with the car performing well and the plugs looking good with no logs of misfires.

Get a compression test done first, you’ll know where you stand then.

The engine comes out the B7 quite easily for the clutch change, you check the pick up pipe then if you desire.

How much oil are you using?

 

[Donfero]

Sorry to reopen an old post Rob but how did you solve this problem?

Sent from my TA-1004 using Tapatalk

 

[Charlie Farley]

The problem just seemed to stop and its been fine ever since, there had been a fairly big oil leak from the brake vacuum pump but i overhauled the unit , maybe it just took a few months for the oil levels to settle down , anyway i've not had any probs since with oil consumption.
Sorry i cant be of more help chap.