They tell me this is common on the 3.2 engines. You get carbon build up on the intake valves because the engine isn't normally run at high enough rpm to sweep it away. Mine has 45,000 miles on it, and began having startup difficulties a year ago. The diagnostic test showed "cold engine misfire" on 2 and 5. Then I had the epc light come on at speed, which was also due to the cold engine misfire I was told, but after some further work was due to worn out sensor switches on the clutch. Several doses of G-17 later, and a treatment of seafoam by the dealer today, I am hopeful we are done with this. If not, the dealer wants to scrub my valves... I'm glad I did not get the automatic transmission!
I hope this is useful to other lost souls...it all is so complicated these days.

 

The problem is the direct injection. Fuel bi passes the valves, so they don't get cleaned. Buildup causes misfires. On the 2.0t, it's recommended to run the engine at 3000rpm or more for 20 minutes or so to help the engine burn off the carbon. The whole issue is discussed in detail in the VW/Audi engine patent on the direct injection. The Italian car makers call it the Italian tune up. AKA, run the car like hell for a while to burn off the buildup.

 

wait ... so how does this effect the automatic differently than the stick model? can this be cleaned DIY?

 

there are DIY's for this, both with the induction cleaning method and the valve scrubbing.

the induction method uses a high pressure to spray the cleaner into the intake manifold to atomize it while the engine is running which then pass on and through the valves.
- look up induction cleaner system.

- while this may work, its not going to be as clean as it would be if you took the intake manifold off and cleaned it that way. this is because some of the oil carbon will have been "baked" on and is harder than newly forming carbon.

not sure why auto vs manual has anything to do with it.