Audi A5 3.2 v6 FSI - carbon issues?

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i have been thinking about buying a 2010 audi a5 with the 3.2 v6 engine. however, in doing some research, it looks likes these audi/vw direct injection engines suffer from severe carbon buildup. Some say this v6 has worse issues than the audi 2.0 4cyl engines (which is available on an a5 for the first time with model year 2010).

Others have said it was a faulty cyclonic system that has caused these issues and audi is now having the system replaced when these cars come in for repair. i have no idea if this is a new part or if they are just replacing in case it was a faulty part. do any of you know???

so, does (will) the 2009/2010 audi a5 with a 3.2 v6 fsi engine suffer from this carbon buildup? is the only "solution" to reducing this issue being to use an oil like redline or biosyn with a 5k oci? do any of you know a better oil to use that is fuel dilution resistant?

any other thoughts?
 
My thought would be to not recommend any car that has an engine that is commonly known to have specific issues. The 2.0T engine has more torque than the 3.2, by the way. Since you will not be driving faster than half the top speed of the car, unless you track it, I see zero reason to even consider the 3.2 engine.
 
more thoughts please, particulary from those of you who own an audi/vw direct injection engine. though is suppose any direct injection engine might suffer from this issue.
 
I have a 2007 A6 with the 3.2. I only have @15k miles on it. I learned about this AFTER my purchase. I looked around on the web and saw only 1or 2 issues with the 3.2. I have seen some issues with porsche and VW EOS. Go to audiworld.com and you will see many examples with no issues. The car is covered by a 4 year warranty, you will be covered under warranty if you have an issue. If it is an issue trade it on something else. Each car has its own specific problems and if you read all on the 'net you will not buy anything(BMW HPFP, Mercedes reliability..etc)

Besides it seems more cars are coming with DI these days. Hey we all can go back to carburetors...right??
 
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I second what mori said about the 2.0T. I drove the 3.2 in r32 form and the 3.6 and I like the 2.0T better than both. It is a blast to drive. Different power delivery altogether. If you like linear delivery you may like the 3.2 better. If you like to feel the punch, you may like the 2.0T better. It just feels more alive to me. Just have to try both on that car to see what u like better. Also 2.0T has tons of pretty low cost tuning options to get lots more power if you want. Mpg should be much better with the 2.0T

In regards to intake valve deposits, I would pm Rl_RS4 or track him down on one of the audi boards as there is probably no one that knows more about the intake issues than him.

Some very easy/low cost preventative options that can help but will not solve the DI valve deposit problems:

1) Use a low volatility and good cleaning oil
2) Seafoam through the intake at every oil change (I posted a diy for the 2.oFSI in the maint. subforum but was about 6 months ago so you might have to search)
3) Regular italian tuneups (VW claims int the engine patent that running at high rpm for over 20 min will burn off deposits but I think it will only help a little)
4) Catch can (all kinds of flavors out there)
5) Fuel injector cleaner in the gas to deal with fuel injector deposits (will not help with intake valve or intake deposits)

More difficult/expensive "helping but not solving options"

6) B6 induction service or similar
7) water/meth injection
8) remove intake and clean valves every 50k or so

Some one-time-fix-the-problem options:

1) bypass pcv and route to exhaust (example for 2.oFSI is posted in maint. subforum)
2) Run a catch can that vents to atmosphere (may build up acids in oil? may have smell or freezing issues?)
3) Run a "down tube" or "road tube" that vents to atmosphere (zoomzoom uses one on his 2.7tturbo) (may build up acids in oil? but zoomzoom's oil looked great)
 
Saaber, the R32 has a VR6. The Audi has a 90º V6. Two completely different engines sharing only their volumetric numbers.

Driving a R32 and a A5 wouldn't exactly be apples to apples comparison with regard to engine performance.
 
Originally Posted By: FowVay
Two completely different engines sharing only their volumetric numbers.


Ahh I see, I just assumed it was the same with all the cross swapping audi and VW does.
 
it seems that all cars are headed in toward direct injection. so unless someone comes up with a better design, we are all screwed. i hear if you get an oil that resists fuel dilution it will reduce your buildup. true? Which two oils resists fuel dilution the best?

Actually the other car i am looking at is a bmw 135i/335i. They have the same direct injection engines, so one would assume they will suffer from this issue to one extent or another. of course, they also suffer from extreme premature hpfp (high pressure fuel pump) failure. bmw extended the warranty on the pump for 07/08 years, but nothing for 09 (or 2010) owners. Thats bad. I know 09's hpfp are dying in as little as 900 miles.

So again i ask, is there a fundamental issue with the vw/audi design or was it a bad part that has since been redesigned? They have had direct injection engines for a while now, one would assume with each model year they would tweak or fix things to reduce this issue.
 
PVC gunk going into the intake + No fuel to wash valves = deposits. So it is a fundamental problem of DI to a large extent. We know VW, Audi, and Porsche engines have the issue but there is not enough info. out there to say which designs of other DI engines have the problem and to what extent.

We know from Rl_RS4's work that the deposits happen in as little as 800 miles and are very noticeable at 2000 miles even after going through audi's cyclonic oil seperator.

The cleaned valves:

clean3.jpg


after 2000 miles:

IMG_2054.jpg


We also have evidence of VW DI engines with deposits despite having a catch can and meth/water injection.

...I would take the 135 over the others based on driving dynamics.
 
This issue might require an engineering solution such as (mentioned above) routing PCV gases to the exhaust just ahead of the catalyst, perhaps using a positive displacement pump of some kind that operates at low temperature so the stuff doesn't bake.

(and a cleanout port in the exhaust across from the entry tube, which will get gummed up over time)
 
saaber1, i have driven all the newest cars on the market in the last 3 months (except the 2010 a5 2.0). This inludes the latest bmw z4 3.5, bmw 335d, bmw 335i, bmw 135i, mb c350, mb e350 coupe, audi a4 2.0, audi a5 3.2, infiniti g37, infiniti fx35 and the nissan 370z.

i still say the infiniti's are the best overall value and the best built cars on the road, but i already have one, so i am not going to get a twin.

bmw 335d's torque has to be driven to be believed, i would take it over a 335i any day. 135i is small and lightweight and was a blast to drive (convertible). bmw z4 is sluggish, shouldn't be, but it is (drove it 2 times).

mb cars were nice, i liked the c350 better than the e350, but thats just me. both are underpowered.

audi a4 2.0t, imho - bland. poor steering, funny sounding, average looks.

audi a5 doesn't have the power most of the other cars do, but it has the best looks, inside and out. the new 3g mmi is the best navigation of all the cars i have listed. i think it would be a nice change of pace, though i do consider it a bit underpowered as well.
 
Good info on the 335d. Never tried that but I'd like to. I agree about the a4 and about the looks of the A5. Saw a real nice medium Blue S5 the other day in front of a cafe. Gorgeous car but the owner was a little too proud of it (hanging out next to it, making a show of it, etc.) if you know what I mean. I think one of the nice things about the A5 is it is beautiful but not real showy or vulgar at all. It's refined and subtle looking IMO. Just my opinion.
 
Originally Posted By: mikeinaustin
audi a5 doesn't have the power most of the other cars do, but it has the best looks, inside and out. the new 3g mmi is the best navigation of all the cars i have listed. i think it would be a nice change of pace, though i do consider it a bit underpowered as well.


How about an S5 then? Although I've heard the waiting list is getting pretty ridiculous...
 
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