A4 1.8T Q (B6)- SLUDGE problem confirmed

[Dan DiBiase]

--- Tony Hoffman <tfh400036 at yahoo.com> wrote:


> Art,
>  
> Ok, I'll start by saying I just quit working at the local Audi
> dealership, and got some very interesting news on this problem while I
> worked there.

> The reason for the sludging, according to Audi, is the lack of knowledge
> about proper cool-down procedures of a turbocharged engine. If you shut
> down the engine with the turbo hot, it "cooks" the oil. This cooked oil
> gets deposited in the engine, as well as the turbo. Why did we not see
> this same problem on the 5000/200's back in the day? Because they held
> more oil, and had larger turbos that didn't get nearly as hot. Now Audi
> uses very small turbos for very quick spool-up, and they get hot quick.
> I've made a 1.8T turbo glow in six minutes from startup!! It took about
> 25 minutes and some serious "ticket driving" to do that to the chipped
> 5ktq. Generally, nowadays, a lot of people are going to use the turbo
> hard in a 1.8T, because you need it to make the power to get around
> town. 
>  
> Most salesmen don't know about turbo cool-down periods, much less to
> explain it to a customer. Therefore, we have a bunch of 1.8T cars that
> were run hard on conventional motor oil with 10k oil changes and zero
> cool-down. Tell me if that doesn't sound like a recipe for problems. All
> I can say is this, flush it, and try to have the oil pump replaced. As
> for the 10% over on mileage, if it's the case, I can see why the dealer
> could have problems with it. 

Interesting info, Tony (I edited your post).... I was always amazed that
the 1.8t only took 4.2 quarts (or I guess it's just under 4.5 with the new
larger filter) of oil. I can't remember having a car that took les than 5
quarts in the past - even my '95 Jetta with the very understressed 2.0
engine took 5 quarts. 

Dan D
'04 A4 1.8Tq MT-6
Central NJ USA