Q3 2017 1.4T FSI excessive white vapour emmisions from exhaust

reefclown

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Just purchased my first Audi as the old VW was getting a little tired after 12 years.

Picked up a 2017 plate Q3 1.4T FSI from Lookers with 13k on the clock, and in general, am quite happy with the car, but...

It puts out, what to me is an excessive amount of white Smoke/Water Vapour from the exhaust especially when reversing.

The car generally gets used twice a day doing a 10-15 minute hop to work and back and on most weekends gets some longer trips

If I take it for a 40 min motorway trip then the fumes subside otherwise it's pumping visible vapour all the time. Never had this with any prior vehicles and seems a little odd to me. Even after a long journey the following morning it's back to fumes, as such I would expect all similar Petrol Q3's to exhibit this behaviour on a cold start, so very interested in others experience.

I took it to the dealership with some video's of the issue and their conclusion was that there are no codes showing, nothing un-towards from an emissions test and visual inspection. They state it's normal Water Vapour emissions due to the car being used for short hops.

Does anyone have an opinion on this or experience of doing short journeys resulting in steam/vapour from the exhaust even 15 minutes into driving?

There is no smell from the emissions and on asking the dealer they are sure it's not oil or coolant related.

Would really appreciate any recommendations on how I can get a concrete conclusion and the next steps I should take.
 
It is happening with my Q2 at the moment. Its just vapour etc being burnt off. Wouldnt worry.
 
Thanks for the reassurance, it's just strange that I see a lot of petrol Audi's on the road that don't look like they are stream driven, wondering why some do and some don't. I've gone as far as standing out by the roadside for 15 minutes and observing cars in general to get a feel of "what normal looks like".

There has got to be some characteristic that causes some petrol vehicles to create more vapour than others, over and above the user doing short journeys.

Be really interesting to get some concrete info.

Assuming that there is no coolant or oil burning issues and the emissions are confirmed as water vapour, also no other untoward signs or OBD codes

from scanning the forum 'apparent potential causes could be

a) Pre Cat O2/Lambda sensor
b) Turbo issue
c) CAT issue
d) blocked exhaust draining

but wouldn't a code be thrown for all of the above?

I'm not a mechanic by any stretch of the imagination, but slowly realising that it's a really interesting area, not sure if it's an art or science though :)

What really bugs me is that my prior 1.4 Polo in the 12 years I've had it was almost permanently clear of any visible emissions. A few mins on a very cold morning at most.

On an optimistic level, maybe cat's are just getting better and doing their job and the steamers are just highly efficient well-tuned exceptions
 
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Water vapour is common on short trips.
Only worry if that vapour has a tint to it. (Blue or black)
 
It's normal.

The white vapour is steam as the exhaust system will never get properly hot with those short journeys so the condensation that occurs in the exhaust system means that there is water lying in pools within the silencer boxes - a longer run would boil the water off and then there would be no steam...

As an aside those short journeys are hard on the car's engine from a wear point of view - the most stressful part for an engine is the period between starting and reach operating temperature. Everything starts off cold/low oil pressure/rich fuel mixture etc.
 
Thanks for the confirmation. What I don't understand is that after a 1-hour motorway drive all is fine. If I then take the car out after a few hours of it sitting in the drive, it still produces a lot of vapour. I'll monitor the coolant reservoir over the coming week as see if it changes at all, i doubt it will as i can't really smell anything from the emissions.

I've ordered an OBD unit just for the interest and will monitor to see if anything untoward comes up.

would it be worth asking Audi for an identical model vehicle to use for a week and see if that's any different? The issue is, even if the temp vehicle produces limited/no vapour, where does that leave me? does it prove anything at all?
 
A one hour drive on the motorway get's the exhaust really hot - dries everything off. Don't forget - when you stop and turn the engine off the exhaust tail pipe is open. The cool, moist air is drawn back into the warm exhaust system and condenses on all that metal...that's where the moisture that you see as steam comes from.
 
I'd find this perfectly acceptable if all horses from the stable exhibited the same characteristics, but I don't see this as being the case.. if I drive onto a customer site and my vehicle looks like a steam engine if creates a perception ( rightly or wrongly), if a customer feels my vehicle is neglected ( through visual perception) it potentially puts me immediately on the back foot. I highly doubt if this is Audi's objective, buts its where I am, I would like to understand what Audi expect from their vehicles (new or old), I would like to think it's not what I am experiencing. But having said that physics and chemistry are what they are, I seriously doubt that Audi's intention was to make steam engines (even if the signs are synonymous with efficiency) without a campaign to state so. The vehicle I am driving is definitely an outliner case, it's just a case of understanding why.
 
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It happens this time of year.
11 years ago someone had the same issue in November :)

https://www.audi-sport.net/xf/threads/fsi-2-0-steam-exhaust.63289/

My wife once said “look at all the fuel ******* out of that cars exhaust!”
“It’s water/moisture dear”
“It runs on water?”

startrek-picard-facepalm-700x341.jpg
 
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I'd find this perfectly acceptable if all horses from the stable exhibited the same characteristics, but I don't see this as being the case.. if I drive onto a customer site and my vehicle looks like a steam engine if creates a perception ( rightly or wrongly)…..

One of the perceptions might be that you live so close to the customer site you could have walked!:tearsofjoy:
 
Because of the extremely high humidity levels at the moment the air is too dense to absorb water vapour, thus at this time of year this discharge of vapour is more noticable. My car is producing the same so it is nothing to worry about...