Excessive oil consumption A4 2.0 BLB PD TDI

[nruff]

Hello Guys,

I'm new to the forum and I've seen loads of useful tips about Audis.
I have a new problem on my A4 B7 2.0 pd TDI year 2006, engine: BLB total mileage: 165.000Km. (no dpf, egr off)
The symptom is really huge oil consumption the oil literally disappearing: roughly 1 liter engine oil within 30 km - sometimes even worst, i barely got home 20km from my place, needed to refill within every 10 km (oil minimum warning kept coming and the oil stick was always at the minimum - so no sensor error).
There are no typical symptoms: no oil spills in the compartment or under the car, no a single drop of oil under the car or on/around the engine, not on the belly pan. No oil around the crankshaft seal, no oil around the intake manifold, no excessive oil in the turbo downpipe.
No excessive smoke. Perfect idle, perfectly strong engine (at least no signs of power loss). No error codes.

I'm totally exhausted of this car... i bought it few months back and already spent a fortune on. This is a new symptom... I was regularly checking the engine oil level and topping up. Before I could manage to measure the oil consumption and the car consumed about 0.1 liter engine oil on 1000km which is perfectly normal. But then it started... if i multiply the current engine oil consumption at the current stage the result would be 30 liter of engine oil within 1000km which is half of the gasoline consumption within 1000 km

Any advice?

Thank you very much!

 

[Gazwould]

Maybe excessive engine and turbo wear to engine due to the oil pump drive previously being lost but just about saved .

 

[NHN]

That's a shxt load of oil to disappear internally, if it's being burnt of it has to be visible through your exhaust.

 

[nruff]

Maybe excessive engine and turbo wear to engine due to the oil pump drive previously being lost but just about saved .

Dear Gazwould, at 140.000km (87.000 miles) when timing belt and tensioners among with water pump has been replaced. With preventive manner the hex shaft also was replaced. Since then no excessive oil consumption has been monitored. (about 1 liter/10.000 km - 1 quart / 6200miles)

 

[nruff]

That's a shxt load of oil to disappear internally, if it's being burnt of it has to be visible through your exhaust.

Dear NHN, sure! The garage is hopeless and I'm getting hopeless too. Currently they are dismantling all pipes and engine parts, but so far no signs of the lost oil. Any guess or past experience would be a great help on this.

 

[Gazwould]

Dear Gazwould, at 140.000km (87.000 miles) when timing belt and tensioners among with water pump has been replaced. With preventive manner the hex shaft also was replaced. Since then no excessive oil consumption has been monitored. (about 1 liter/10.000 km - 1 quart / 6200miles)

The hex shaft replacement isn't preventative maintenance as it's primarily a #2 balancer shaft keyway issue through poor fit of not being hexagonal , deep enough and hard enough , then there's the chain tensioner etc .

 

[nruff]

The hex shaft replacement isn't preventative maintenance as it's primarily a #2 balancer shaft keyway issue through poor fit of not being hexagonal , deep enough and hard enough , then there's the chain tensioner etc .

View attachment 256118

Thank you Gazwould, but I assume even if the oil system have failed once, the symptoms would come right after the fix. However it is still a misery where the oil goes because that amount of oil shall be visible somewhere especially if the turbo has failed.

 

[Charlie Farley]

if you needed to refil 1 ltr after 30km then you have a serious problem.
It is either leaking externally or burning it.
If it is burning that much oil then there will be visible signs of it somewhere, if via combustions you have smoke pouring out the exhaust .
If via a leak then you will still have an oil trail.
Depending on where you park the car and on what surface a leak of that volume will appear at some point allowing for it getting being blown all round the engine bay.
Its either burning or leaking and in those volumes, it is not good.

 

[B7Tourer]

I am very surprised there are un-modified BLBs still around. But in almost every case I have heard of when the pump failed the oil level was normal, it was total catastrophic loss of pressure and not oil that killed them. So whilst it is highly likely the chain/hex key/pump needs serious attention, there is clearly other serious damage too and that must include piston rings, turbo (a bad turbo can dump a lot of oil very quickly) if you are absolutely sure there are no leaks at all. Even though I am getting the modified hex key fitted to my BRE engine, at the same time as the cambelt, in a couple of weeks, it is well over 230K miles/365,000KM and it uses virtually no oil between services - I'm hoping I'm not wasting money by it being already have been done, since the car runs so well - but there is no other way to be sure and I want to keep it for a long while still.

 

[Gazwould]

Just a key ?

 

[B7Tourer]

Just a key ?

No KMB, kit 9, modified balance shaft too.

 

[Gazwould]

Always best to say Kit as someone could follow suit .

 

[NHN]

Losing 1 litre for 30 Kms is insane, it has to be visible somewhere either as oil leaking or smoke, it's impossible to lose that much & nothing to see.

 

[Charlie Farley]

Losing 1 litre for 30 Kms is insane, it has to be visible somewhere either as oil leaking or smoke, it's impossible to lose that much & nothing to see.

Exactly, it's just not possible to have that level of oil loss without visible indicators of some description.
There is oil loss and oil consumption, I really can't see it being consumed at that rate through combustion loss, if it is then you need a new or rebuilt engine asap.
More likely to be a leak and you have missed it but given the amount you have lost it will be visible somewhere.

 

[NHN]

I agree, you can't be burning that much & if so, as said that's a new engine or rebuild, damn that's allot.

 

[nruff]

The turbo is very suspicious. Is it possible that the turbo leaks that much oil into the inter-cooler (from the compressor side)? However the downpipe was loose, so it can be that atomized oil went out the downpipe at the flange of the turbo, and the rest went to the combustion among with air? I forgot to mention that the oil consumption as more as I use the car on higher RPM's. On low RPMs around 1.800 almost no consumption, from 2.000 RPM the turbo starts whistle louder than before and the minimum warning comes soon.

 

[B7Tourer]

On low RPMs around 1.800 almost no consumption, from 2.000 RPM the turbo starts whistle louder than before and the minimum warning comes soon.

Then it is your turbo, most definitely. It is to be remembered that the oil pump critical issue, mentioned before, would rob the top of the engine with any oil, including the turbo. So it is a red herring in this case. But a stuffed turbo that has not been replaced, after a fixed oil pump, might suck oil, badly as in your case. Replace that turbo, as a matter of urgency and see what happens then.

 

[faby01]

Tandem pump? Check fuel filter, if it's black you have oil in the fuel.