S3 2010 S-Tronic with turbo lag when changing gear?

[OliS3]

First of all i'm new to this forum so hello everyone!

I've found a 2010 S3 with S-tronic I really like but when I was out on the test drive I noticed when changing gear there was quite a bit of lag. Best way I can explain it is flat out in 3rd the gearbox changed to 4th and it took about half a second for the turbo to kick in again. Surely at 5k rpm the spool should be nearly instant with that load? I've watched a few youtube videos and it seems instant.

The dealer says they will fix it but has anyone heard of this before or got any ideas what it could be?

Thanks, Oli

 

[NHN]

Welcome Oli

As long as dealer will warranty it, to fix aswell, then I would seriously consider it, also there are gearbox maps you can have potentially that can liven things up along with an engine remap, which may help resolve the issue if they find no problems, anyway stipulate, should you purchase, it must be resolved or car comes back etc.

 

[OliS3]

Welcome Oli

As long as dealer will warranty it, to fix aswell, then I would seriously consider it, also there are gearbox maps you can have potentially that can liven things up along with an engine remap, which may help resolve the issue if they find no problems, anyway stipulate, should you purchase, it must be resolved or car comes back etc.

Thanks for the quick reply, they have said they will fix it but I am just concerned as dealers seem to say anything to get your money off you. I was hoping someone might of come across it before and I could point the engineers in the right direction. Other than being a boost leak or stuck turbo vane I can't find anything else on this forum.

 

[IceHanger]

Mine does this but at the top end of the rev range in manual mode and the DSG has upshifted itself, I did some logs and came to the conclusion I was hitting a stage one limiter slightly or run out of boost. Audi also suggested the same.
Hopefully when I get round to mapping, it will cure it.
The rest of teh rev ranges/changes are fine.

Have you tried it in Manual or sport?

 

[NHN]

Thanks for the quick reply, they have said they will fix it but I am just concerned as dealers seem to say anything to get your money off you. I was hoping someone might of come across it before and I could point the engineers in the right direction. Other than being a boost leak or stuck turbo vane I can't find anything else on this forum.

Then as I advised, get it stipulated you have noted this issue & they are to resolve/fully investigate this & should the fault worsen, then they would be required to fix it at such time, get in writing.

 

[jaydav2306]

Cant say that I have had this with mine, by fixing it I assume they would mean a new mechatronic unit, I would try and find one without the lag or test drive another see if it's normal

 

[OliS3]

Mine does this but at the top end of the rev range in manual mode and the DSG has upshifted itself, I did some logs and came to the conclusion I was hitting a stage one limiter slightly or run out of boost. Audi also suggested the same.
Hopefully when I get round to mapping, it will cure it.
The rest of teh rev ranges/changes are fine.

Have you tried it in Manual or sport?

I doubt it is the limiter as it is in the next gear it loses the boost and pulls fine to redline. I'll try and speak to an engineer and see what they have to say about it.

 

[IceHanger]

I doubt it is the limiter as it is in the next gear it loses the boost and pulls fine to redline. I'll try and speak to an engineer and see what they have to say about it.

I meant you just brush the limiter in one gear as it changes up, so the engine has cut power briefly and has to build it again so it would be felt in the next gear.
It sounds like thats not your problem anyway.

 

[OliS3]

I meant you just brush the limiter in one gear as it changes up, so the engine has cut power briefly and has to build it again so it would be felt in the next gear.
It sounds like thats not your problem anyway.

No that does sound similar. I only noticed it at the end of the test drive so I'd need to drive it again test it properly.

 

[Rick @ Unicorn Motor Dev.]

Power should be completely smooth if accelerating flat out. The only delay that can sometimes occur is if you shift to a gear the box isn't expecting, and you get a little lag. I've also come across remapped cars which haven't been done right which have this issue, but I doubt that's the case here. Suggest you drive it again to make sure, and drive another to compare it to.

Rick

 

[OliS3]

Power should be completely smooth if accelerating flat out. The only delay that can sometimes occur is if you shift to a gear the box isn't expecting, and you get a little lag. I've also come across remapped cars which haven't been done right which have this issue, but I doubt that's the case here. Suggest you drive it again to make sure, and drive another to compare it to.

Rick

I thought as much, from what I've read the DSG box constantly transmits power to the wheels during a gear change so the load to the engine should also be constant meaning the turbo should stay spooled.

I can't think what would cause it though? At first I thought boost leak but now i'm thinking more a sensor error?

 

[nluk100]

First port of call would be to take the DV apart and check it for leaks / splits (depending on the version you have fitted). Has the car been mapped by a previous owner that you are aware of, as there are known issues with later s-tronic cars and lag between gear changes with some remaps.

 

[OliS3]

First port of call would be to take the DV apart and check it for leaks / splits (depending on the version you have fitted). Has the car been mapped by a previous owner that you are aware of, as there are known issues with later s-tronic cars and lag between gear changes with some remaps.

As far as I know the car hasn't been remapped.

Just spoke to the tech and they are saying that it is normal with the 2L turbo and S-tronic combo I've asked him to drive it and explained the problem again and he is going to call me back later.

I guess until they admit there is a problem i'm going to walk away which is a real shame as the car, colour and spec is perfect

 

[OliS3]

As far as I know the car hasn't been remapped.

Just spoke to the tech and they are saying that it is normal with the 2L turbo and S-tronic combo I've asked him to drive it and explained the problem again and he is going to call me back later.

I guess until they admit there is a problem i'm going to walk away which is a real shame as the car, colour and spec is perfect

The head tech has drove it and he agreed there is an issue so they are going to look into it tomorrow and will get it sorted so I can buy the car.

Can't wait

 

[Rick @ Unicorn Motor Dev.]

It will be interesting to see what happens. Could be an issue with the mechatronics unit.

Rick

 

[NHN]

Not heard of this on a 2010 yet, but be interested to know.

 

[OliS3]

I'll keep you all informed. I've just read up on the mechatronics unit and I don't think it was that as the changes seemed fine. The issue was more with boost coming in.

I'll see what they say today and I can always test drive it again now I know more about it i'll have an idea on what to look for.

 

[jaydav2306]

Sounds more like a DV issue

 

[OliS3]

Sounds more like a DV issue

Just causing a boost leak?

 

[jaydav2306]

Just causing a boost leak?

Yeah sort of, the issue you described I sort of had, around 4-5K flat out it would just stop, then go again, I changed the DV to a revision D part from Audi and havent had the issue since, now my car is a late 2009, finished being built 30th June 2009 I believe and the car you drove a 10 plate so it could be a similar issue.

 

[OliS3]

Yeah sort of, the issue you described I sort of had, around 4-5K flat out it would just stop, then go again, I changed the DV to a revision D part from Audi and havent had the issue since, now my car is a late 2009, finished being built 30th June 2009 I believe and the car you drove a 10 plate so it could be a similar issue.

Thanks for the update, I wish I could drive it again as I didn't force it into a gear and run it from low revs to redline. I should hopefully have an update from them later on though. I think it is only a small issue but i'm not committing to spending 20k without it being perfect.

 

[nluk100]

A faulty DV will cause the turbo to stall between shifts, hence appear as lag.

 

[OliS3]

A faulty DV will cause the turbo to stall between shifts, hence appear as lag.

Thanks, it does make sense. Should the DV make any noise as standard as I never heard anything on the test drive? I know they normally recirculate as standard but in my EVO i could still hear some noise.

 

[OliS3]

A faulty DV will cause the turbo to stall between shifts, hence appear as lag.

Also is there any easy way to test it is working correctly?

 

[jaydav2306]

A faulty DV will flutter so its an obvious stalling noise, with the windows down and my new DV on after 3K revs I just get a really nice pitch constant whistle and you can hear it on constant boost, no flutter at all, it's an awesome sound, even nicer with the S-Tronic as you get the exhaust burp when you change gears I love mine

 

[OliS3]

A faulty DV will flutter so its an obvious stalling noise, with the windows down and my new DV on after 3K revs I just get a really nice pitch constant whistle and you can hear it on constant boost, no flutter at all, it's an awesome sound, even nicer with the S-Tronic as you get the exhaust burp when you change gears I love mine

I can't say I noticed a flutter noise but that doesn't mean there wasn't one. I did notice the exhaust burp though which I loved

 

[OliS3]

I've spoken to them again and the tech said he drove another S3 T-tronic and he could see what I meant (Worrying as I noticed it and I've never driven any kind of S3 before) He said he reset the gearbox learning memory and it has solved the problem. I need to get over there to drive it again but could that really solve it?

Thanks, Oli

 

[JS3]

I have a 2010 s-tronic, cant say I have noticed this lag, it is very smooth under acceleration and I have the rev D valve I believe. Next time you test drive can you check the valve quickly? I believe (from memory) its a quick check under the bonnet but do a search on here and it should tell you where to find it. Somebody may correct me though!

 

[OliS3]

I have a 2010 s-tronic, cant say I have noticed this lag, it is very smooth under acceleration and I have the rev D valve I believe. Next time you test drive can you check the valve quickly? I believe (from memory) its a quick check under the bonnet but do a search on here and it should tell you where to find it. Somebody may correct me though!

I drove it again today and the conditions weren't ideal but from what I could tell the issue had been resolved or reduced a lot.

I agreed to buy the car on the basis I had a letter from the dealership showing I had reported the issue and that if it hadn't been resolved they would resolve it under warranty in a reasonable time. Hope I've done the right thing.

 

[Robert Williams]

Bit of an old post i know but was it ever discovered what was wrong? Mine occasionally shows the same symptoms.

 

[OliS3]

Has yours be remapped?

 

[Robert Williams]

Has yours be remapped?

Not that I know of. It was previously owned by Audi so I wouldn't imagine so. Have you still got he issue?

 

[OliS3]

Not that I know of. It was previously owned by Audi so I wouldn't imagine so. Have you still got he issue?

I bought mine from Audi 2nd hand with the issue, after taking it to another dealer they confirmed (to the best of their knowledge) it had been remapped and took the car back in exchange for another. The other dealer confirmed it had a lot of warranty work so I wasn't going to say no to getting rid of it and got a car that had no issues for over 2 years

 

[Robert Williams]

I was hoping you were gna say you found out what it was lol! Oh well mine is fine but it just does it every now and again. Maybe it's the DV. I haven't changed that. Everything else has been done so all I'm thinking is yes it is mapped or the turbos showing signs of fatigue.

 

[OliS3]

Mine did it every time, when my 8V changes you feel the slight loss in power but it completely dropped off like a manual in the car in question and took half a second to respool. Hopefully someone else can help

 

[Robert Williams]

That's interesting to know Oli. I've ordered a new DV and will replace it as a preventative measure but other than that I think I will probably leave it until I get a fault or something else! Thanks

 

[OliS3]

That's interesting to know Oli. I've ordered a new DV and will replace it as a preventative measure but other than that I think I will probably leave it until I get a fault or something else! Thanks

The dump valve would make sense, fingers crossed it is that

 

[Robert Williams]

Well it is on 87k now and I doubt it's been changed either.

 

[Robert Williams]

Just letting you know i've fitted a new DV and all seems well! On comparison the old DV felt a bit slack when i depressed the piston compared to the new one. It was a Revision D valve.

 

[grainqey]

I briefly had a revision D on mine and I prefer they way the revision G holds the boost, its rubber rather than plastic so seals better!

The issue that was described could be the clutches needing to re-adapt I suppose for the wear so limiting torque for longer however it did this on mine with the blow-off spacer on so it seemed to overboost after closing the recirc valve (seemed laggy but then over compensated for the temporary loss of boost)