S4 AAN smoke (videos)

[Macchris]

Well when i buy this car for parts one year ago i make 50 kms to come back home and my wife follow me with other car and she had not seen any smoke.

Like you can see in the video here when i make test with the car in front of my house :


but then some weeks after buying smoke appears (i dont drive the car since the first video)


Any idea what i must check ? i have changed Motronic (it was a MTM chipped one, i put a genuine one), lambda, no Vagcom problem detected (apart lambdasonde before i change it)

injectors maybe ?
thanks for your help guys
Tof

[Macchris]

Well the videos are not working at home so here's the direct links :

https://www.youtube.com/watch?v=9L8rwonPvQI

&

https://www.youtube.com/watch?v=9zTs-o7peVI

[SteveH]

White smoke is typically water getting into the system. Head gasket, porous head, etc?

[Macchris]

Thanks Steve,
There is no water in the oil, no oil in the water, no combustion gas into water reservoir, ... the smoke lookslike more light grey than completely white

[SteveH]

I had a porous head on my 3B. Water was leaking from the head coolant channel, through the head and into one of the exhaust ports. It didn't cause any issues other than slow coolant loss and white smoke. If the caar hasn't been used much for a while, give it a good run and it might just go away.

[hunker7]

Looks like vapour to me. In cold weather that pretty normal. Is it still there when engine is upto temperature?

[Macchris]

yeah smoke is always here even after 30mn running engine at idle.
by the way there is an odour very special, not easy to describe it on internet lol ;-)

Steve, i cannot use the car on the road, must pass technical control are you bet there are manies repairs to do and must pay about 500 euros for the title in my name. For a car i want to parting out (the engine will be the heart of my next GTQ AAN conversion projet) it'll be too expensive

[SteveH]

Only odour I can imagine is coolant being burnt. Can't be oil as it would be blue. Overfueling is typically black/sooty smoke and a rich running smell. Internet doesn't help us here!

[M_GORDON]

Maybe oil from PCV system?

[John.]

There is no water in the oil, no oil in the water, no combustion gas into water reservoir, ... the smoke lookslike more light grey than completely white

.......and sniffer test good too by the look of things.

If it's driving well and not using oil or water, maybe just due to air temperature?

[hunker7]

Till you can give car a proper blast down the road don't worry about it. I always find car runs better after a good drive on a motorway. Like John said, if oil or water isn't disappearing onto worry about it.

[Macchris]

Maybe oil from PCV system?

it could be ? i must check, thanks for info

If it's driving well and not using oil or water, maybe just due to air temperature?

dont think so John as i have started the engine in hot summer too with the same smoke :-(

Thanks guys for your concern

[RichLV]

We have -2 degrees here & mine is constantly blowing grey smoke. Nothing to sweat about.

[Macchris]

With unpleasant smell ?

[RichLV]

With unpleasant smell ?

Only exhaust gas smell. Check if you aren't losing liquids. If not, then disregard it.