Help: Audi Tts - Loads Of Smoke And Won't Move :(

[dr_shabzzz]

I didn't want this to be my first post but I just picked up an Audi TT-S and something has gone badly wrong

The car started to judder around 2krpm and then loads of white smoke out the exhaust followed by more juddering and car struggling to move at all

I turned the engine off and had it towed to a garage...

RAC read the faults and it came up with piston failure on piston 4 (permanent).

Havn't lost any coolant or oil which gives me some hope!

Any ideas what this could be?

Thanks guys

 

[NHN]

Welcome to the site.

Picked up from where?

 

[dr_shabzzz]

From a private seller.

The mechanic hasn't run a full diagnostic yet but apparently it's something to do with blocked fuel or fuel not getting to a cylinder?? He says the white smoke was all fuel (which makes sense as the coolant level is still between min and max.

Any ideas?

 

[Oranoco]

White smoke is water, black or grey is fuel and blue is oil. You don't need much water for white smoke and would be thinking towards headgasket failure but not having the car sat in front of me diagnosis is hard.

 

[dr_shabzzz]

It's definitely fuel...a puddle of it has come out the exhaust and petrol can also be smelt in the oil

Compression is good across all cylinders so have ruled that out

I think it might be either the high pressure fuel pump or dodgy injector pushing too much fuel into the cylinders...I'm not sure if that would explain petrol in the oil though??

Could it also be a lack of spark causing unburnt fuel to pass through to the exhaust? Maybe dodgy coilpack?

I'm not sure which of these places to start and we could end up replacing lots of perfectly working parts and not get to the problem

 

[Oranoco]

Petrol in oil is a symptom of bore wash where the fuel has passed by all three rings of the piston from the combustion chamber to the sump. It thins and breaks the oil down and usually requires a full engine build to effect a repair.

 

[dr_shabzzz]

There was no sign of a problem - it happened all of sudden which makes me think it can't be piston rings? As I would have thought those wear out over time?

The fuel would only have been in the oil for 10 seconds before I saw the smoke and turned the engine off - not enough time to cause damage- good compression on all cylinders confirms this

I don't want to keep replacing bits and it doesn't fix the problem...it's getting expensive lol

 

[Oranoco]

The fault isn't with the rings and likely to have been perfectly fine (and again oil smoke is blue not white), it's the vastly excessive quantity of fuel present that causes the issue. I guarantee that is how the fuel has contaminated the oil. If the cylinder that washed isn't damaged I would be gobsmacked, far more likely your mechanic hasn't discovered any damage yet.

To be brutal mate this is going to cost a wedge to rectify.If it doesn't it's a bodge up and won't be lasting long

 

[FactionOne]

There might not be block(>bore) damage in this case.

I'm told by a reliable source that there's a [reasonable] chance on a 2.0 TFSI that the high pressure fuel pump up top might've dropped its guts; and when they do, they tend to cause all the symptoms described.

The 'good' news is that if that's the case, it'll only be work to the head side of things to repair it (the pump itself, and possibly associated bits up to a full head; but the really expensive stuff might well be alright)

R