raj99

Pretty well spot on. There's lots of info on the interweb about this originally coming from Ferrari, since those owners tended to overly pamper their vehicles. But as pointed out, if you already have the deposits caked on well, the 'Italian tune-up' won't be of much value.

raj99

Mine is a non-FSI 4.2 A6 (06), so I don't have the notorious issues of the 3.2 and like you, have advised people of the perils of that particular engine. In fact, my dad is currently in the market for a Q5 and although the 3.2 are cheaper, I've advised that the only choice that meets his budget and on-going ops/headaches is the later model 2.0T.

mishar

Carbon deposits come from oil getting into the intake and compression chamber. It pass valve steam seals, piston rings and oil separator. It pass more under a higher load. Also deposits more when engine is warmer. By the way, intake manifold and valves won't get much warmer under a higher load. Not nearly hot as self cleaning oven. So Italian Tuneup makes it worst, especially on FSI engines.

So what good it can do? It can warm up spark plugs and burn deposits from them. That helps with old design ignitions and plugs, especially on high output engines like Ferrari that use very cold plugs.

dvs_dave

Inlet valves get up to around 750-800F which is right up there and enough to burn crud off. Trouble is keeping the temp up there for long enough which you can't.

Regards the other aspects of an Italian tune up, it'll also blow out deposits that do build up in the combustion chambers and soot from the exhaust manifolds over time, especially with a city car. It'll also give the injectors and fuel system a good blast through which again if it's a bit dirty can help clear it out.

My wife's Mini Cooper S which is a DI turbo engine really benefits from a good thrashing every now and then. It spends most of its time in Chicago traffic and below 2k rpm so never gets really hot or blown through. I take it out every now and then and do a few full bore runs up to the redline and it blows a noticeable cloud of soot out the back which clears and the motor noticeably runs better and idles smoother after. All down to crap built up that the Italian tune up improves every time.

Also going back to being a boy in the 80s my dad had an 86 Audi 100 2.3E which was a super high geared econo version in Europe. As a result it never revved very high. Anyway, it started pinging quite badly when on holiday in France so we took it to the local Audi dealership. The tech got into it and took off down the road at full blast, that 5 cyl warbling it's little heart out and a huge cloud of soot coming out of the exhaust. My dad got mad and yelled at the guy when he got back as it looked like he'd just trashed the engine. Anyway, the tech just gave a classic Gallic shrug and went on his way. Low and behold, no more pinging and the engine ran much better. And it gave my dad a legitimate excuse to regularly beat on it.

In other words the Italian (or French) tune up does work and is not a myth.

mishar

Sure it does. Was that 86 Audi?

Jack88

I had a 1980 Buick for a first car, and if I put my foot down and hadn't for a while, it would let out a fairly good puff of black smoke from the exhaust. I haven't had a car with fuel injection do that.

dvs_dave

Fuel injected 86 Audi, as well as an 08 DI Mini Cooper S. My TVR also benefits from a good throat clear too after being in city traffic for a while. Carbon and soot build up is a real thing, that a good thrashing (aka Italian tune up) will clear, even with modern engines.

86 Audi had carbon deposits in the combustion chambers that were retaining heat (like charcoal as an analogy) and when coupled with a bit of compression was enough to cause the fresh intake mix to detonate prematurely. I still remember the sound now and I must have been about 7 or 8 at the time....sounded like maracas under the hood.

Audi fan ever since though. Dad had 2 C3 2.3s, then a C4 2.8 Quattro, and I've had an 8L Euro only gen 1 A3 (which came to an unexpected end on the Nurburgring...oops!), and now my D3.

allenst

see with my 2004 A8 I wanted to learn about the areas of possible carbon buildup and what I could do about them, being aware of using quality fuel, injector cleaner, filters etc etc.

my mindset was, "What else can I do to clean up carbon and where would that carbon be on my engine type. (4.2)

dvs_dave

Pre FSI engines aren't prone to carbon or gunk build up any more than any other non DI engine. Although if you drive mostly short distances in the city, that accelerates any gunk buildup that may occur due to low engine temps, low fluid and gas flow speeds, and the oil being more likely to have a moisture build up. It's good practice and mechanically sympathetic to occasionally give any engine a good blast to clear it out once it's fully up to temp (incl oil!!!) and take the car for a good run to boil off any moisture in the oil.