I still don't recall anyone having this problem. My suggestion would be to make sure you run good gas that has good additives (Chevron and Texaco are the two my mechanic recommends as the two best), and open up the engine a little. According to my mechanic, people who have these kinds of problems are often those who drive in the low revs all the time and don't let the engine operate the way it was designed. Many people think that revving the engine is bad, but the reality is that not revving it enough can be worse. Open it up and blow that crap out! Something that would be interesting to find out is if the people with this problem have the automatic transmission. The auto tranny shift programming operates the engine in too low of a rev range, unless you take charge. Still have not heard of this though!<p>Charles<br>

I'm interesting in buying the 2.8 quattro, but I'm worried about some comments of A4 owners who had serious problems with their valves on this engine. <p>Can anyone share his experiences about this ?<br>

I don't recall anyone here ever reporting problems with the valves on the 30V engine. Some people have had turbo failure on the 1.8T's, and there have been occasional oil leaks and what not, but certainly nothing in any number worth worrying over. Where did you hear about the valves, and what kind of problem? Do you know? I certainly don't think it's anything to worry about.<p>Charles<br>'89, 90Q (96K mostly reliable miles)<br>'98 A4 2.8 Q-Tip (14K, no valve trouble, and really a business car)<br>

<br>Ok, thanks for your answer. My worries came up when I read usenet messages in the audi-newsgroup so I wondered. Personnally I had never heard of those problems, and I think you are right to think that one must sometimes "blow out the crap", that is the carbon that results of a bad ingnition of the fuel. The quality of fuel and low running of the engine must be the other factors to this.<p>C U.

The following message appeared a couple of days ago in the alt.autos.audi newsgroup. It is a very serious allegation, IMHO.<p>Joseph Mettee wrote in message <01bdfef5$30fa6200$7dd74f0c@worldnet.worldnet.att.n et>:<p>>Audi has a BIG problem with the 30 valve, 2.8 liter engine. The three intake valves have a tendency to collect carbon. Ultimately this causes the engine to not start (my `98 A6 seemed to run fine one day but would not start the next and left my garage on a flat bed). According to my dealer, Audi is trying to find a solution but can't seem to come up with one. My big worry is that these valves that don't close as a result of the carbon build up will end up burning!

Audi sez you can use regular, but recommends 91 octane premium fuel. I never use anything with a lower octane count than 92. I've got a mere blissful 8,500 miles on my 30V, and plan on many tens of thousands more.<p>J.Russ<br>98.5 Avant QMS

Blob,<p>I agree with Chuck. I've driven my 98 2.8 30V Tip for over 13,000 miles with absolutely no engine problems. Of course, I drive like a *bat out of hell.* Though I have the Tip, I pretty exclusively use the semi-manual gate. It's rare when I let the revs go under 3500 RPM. I'm happiest when I'm over 4000 RPMs. I always make a habit of fueling my car with Chevron - 93 Octane. I use a different brand gas every four or five times to keep my engine alert :-)..............but I always use 93 Octane.<p>Rick

The use of premium is recommended for the tuning/performance advantages. I have heard in several places that premium gas creates slightly more deposits than regular grades. Some brands have extra detergents/cleaners to counteract this tendency.

No problems here (at 10,700 miles), but I think that we might be ovrereacting. No one has posted an actual carbon buildup problem on the forum yet that I have seen, and I have been reading it for well over a year. There are a lot of owner's represented here, and we see some pretty rare problems reported.<p>These internet discussion groups tend to create "moutains out of molehills." Chances are that some people somewhere have had a problem with carbon buildup. But we don't know how many people this is, what mileage, what gas they used, how they drove, or whether there is something else going on.<p>In past forum discussions, people have done the following, as far as going too far and creating their own news:<p>-Said that Wetterauer is a dead company that is leaving the market.<br>-Decided that the 1999 A4 would be totally redesigned.<br>-Stated that all 1.8T engines would be 180HP for all of 1999.<br>-I'm sure there's more....<p>Obviously, this carbon buildup thing is something we should keep an eye on, but lets not go overboard (yet?)

My early '98 2.8 has been "skipping" intermittently for several months. It's a 175 mile round trip to the closest dealer and, when I finally got there, was told I had a bad spark plug wire. Of course, they didn't have one in stock, but that's another story. A week and another 175 miles later, the offending wire and plug were replaced. The mechanic suggested I change to a different gasoline since what he could see of the combustion chamber appeared very dirty. I use Amoco premium with an occasional dose of Techron so we attributed the buildup to running the engine for so long with that cylinder misfiring. Unfortunately, he didn't look at any of the other combustion chambers so I don't know if the other cylinders are dirty or not.<p>Reading this thread now makes me wonder if the build-up is in all the cylinders. The car seems to run normally. It's 16 months old and right at 20k miles.<p>BTW, I tried to find the Alt Auto Audi newsgroup mentioned in the earlier post but was unable to. Has anyone else been there?

Great engine.

I have to agree with you on that one. It's not a new problem either, an old Porsche race mechanic of mine described exactly the same problem/solution for the 924's (AKA Audi 100's !).<br> Cheers<br> Simon 99 2.8QM (920miles - nearly there :-> )

Premium is usually made with a slightly better "base" fuel stock (for octane rating). Then additive packages are used to PREVENT and REMOVE deposits.<p>However, these additive packages themselves tend to deposit in small amounts. The workaround I have read about in several instances is to switch brands every 5000 miles...rotating between three brands at a minimum. The additives in each brand will go a long way to removing any deposition of other brands' additives.<p>All this is based on several write ups which can be found on the 'net....one in particular is from a chemist who works on gasoline additives for a major oil/gasoline company.<p>steve