rough idle on v10

[bort]

any thoughts or suggestions? i own a v10 have been the original owner and only driver. never tracked. started experiencing rough idle on start up and small loss of power about a month ago. car has 9000 miles now. dealer has had me run audi fuel additive for two tanks and the problem persists. i am getting few answers when i suggest carbon on the valves. i am scheduled to bring car in again for service but no answer from the dealer or audi of america customer service.

[gazza1]

Typical symptom of Carbon build up but at only 9000 miles seems unlikely.

[M3R8]

I've had rough idle on start up twice already, but I find no common thread between the two cases. What are the possible reasons for a rough idle that only happens once in a blue moon?

[SteveR]

any thoughts or suggestions? i own a v10 have been the original owner and only driver. never tracked.

There is your problem right there.

I doubt you have a carbon buildup problem at 9k. I'd just make sure you are only using gas from the Top Tier stations. That fixed a similar problem in my old S4.

[bort]

i agree it sounds odd to me also at 9000 miles. i only have used 92 octane bp gas as we do not have 93 available in the city. the frustration is the run around i am getting. they service technicians say that there are no error codes showing but have insisted that their hands are tied and that all repair authorizations have to come from audi directly. the suggestion that the car must be driven consistently for trips other than commuting has been put forth seems odd. any thoughts that this could be an fsi related engine problem similar to those an the rs4 rs 6 models? audi has sent a letter extending the warranty an additional year for carbon related problems however that does little to fix the isuue. thanks for the thoughts

[KfabR8]

BP - that right there is the culprit. HORRID fuel to use (at least in the US) - and this statement has no political aspect, it's based on usage history. Motocross bikes are notoriously temperamental about the fuel used and I've never experienced more issues and bad running than with BP's products.

Switch to Shell and I bet the issue goes right away. Citgo works well too. Make sure you purchase from a station that has high traffic, as it guarantees the newest fuel, not stuff that's sat in the storage tank for a while. The longer it resides in the storage tanks, the higher the likelihood of of condensation and contamination residing in your fuel.

[SteveR]

Right. BP is horrible gas.

By "Top Tier", I wasn't referring to the octane. Go to the Top Tier Gas website and only buy gas from a station on that list. It should get better after a couple tanks.

[bort]

thanks ill try it. i have a 2010 gt3 rs and should be getting a 4.0 soon. i have been filling at the same station with the rs and no problems. but you guys may be right. thanks for the responses

[maegeri]

On an V8 S4 Avant, I had a similar problem but more severe than your description and it was ultimately diagnosed as a cylinder misfiring from an electrical problem. The car was really rough at idle and there was noticeable power loss. Hope it's not that kind of thing.

[StuM]

We had the same idle in our 09 R8 V8 coupe and now in the V10 spyder. Doesn't last long. I asked my Audi tech about it and he said it's just how the engine reacts until the cat's warm up and the feedback loops all recognize the basic parameters. It's never been a problem for us. Just wait the ~20 seconds it'll take to calm down and drive off. Have fun doing it too!
Stu and Shelby-Girl