I am new to Audi and this forum and have been reading many of the issues regarding carbon build-up in the Direct Injection (DI) engines introduced in 2006. Many of the concerns seem to with the 2008 MY vehicles, and many of the comments are also somewhat dated (old). Is Carbon Build-up (CB) still an issue:
1. with the 2006 and newer Audis?
2. Is there a difference based on MY of production (i.e. 2008 MY) or all Audi DI engines prone to this?
3. Are there inexpensive (I know—what’s inexpensive) resolutions to CB besides the manual decarburizing ?
I have been looking at principally 2006 MY A4s with both 2.0l turbo and 3.2 L NA motors. I have focused on this MY as initially I was told by sales that the DI engines began in MY 2007—this seems not to be the case but DI introduced in MY 2006. I have found some well equipped vehicles in the My (2006) with mileage ranging from 35,000-70,000, but now somewhat concerned about this issue and buying into an expensive problem.
Has VAG admitted that this is a problem and support Audi owners beyond factory warranty periods?
Finally, beside the CB issue are there other know Achilles heel concerns with the cars. They sure are fun to drive!

Thanks
Tdsoup (Colorado and Northern CA)
(Previous 1984/88/95 Porsche Carerra 911 owner, now 2001 Odyssey/2002 Accord/2007 Civic Hybrid and hopefully an Audi A4)

 

Don't really hear any carbon complaints here. Read my FAQ for other normal issues.

 

64,000 miles on my 2.0t "06" and no carbon problems. How hard the car is driven seems to have something to do with it. Babying it can make it worse. Don't need to abuse the car though. Also the 2.0t don't seem to have the complaints about carbon that the naturally asperated engines do. I'm guessing that the higher temps, and pressures of the turbo, help minimize buildup. Audi/VW has info on the engines patent on how to reduce the problem. Basicly if you run the engine at 3,000 RPM's for 20 minutes periodically it helps get the builup off the valves. The patent say's that running at that rpm increases the temperature of the valves to the point that the carbon comes off. Kinda like a self cleaning oven. Here is the link http://www.mycar.net/volkswagen/6866031.html I think it is about 2/3 though the patent. Hitting the 3,000 rpms is not hard. 60 in fourth, and 75 in fifth with get you just over 3,000 rpms.