A4 1.8T Q (B6)- SLUDGE problem confirmed

[Tony Hoffman]

<SNIP>
relating to oil record (specs in manual were for 10k mi intervals and 
mineral oils were allowed and used by Audi):

  11610 - 10K(oil change)

  18769 - at the dealer for service, but THEY DIDN'T CHANGE THE OIL

  24081 - (12471 since last) 20K(oil change, oil pump replaced)(oil 
light on) 

      Aug 2004 - Audi oil sludge letter

  34535 - (10454 since last) 30K(oil change)(oil light on)

      then I got it at 36500

  38081 - oil changed by me (pressure light had come on)

  39940 - Audi oil change (pressure light had come on)

  now It's at 41400 (oil pressure light on)

Today they tell me they took the valve cover off and diagnosed it as 
having a sludge problem. Dealer says Audi won't give them approval to 
replace the engine because of oil changes >10% miles overdue. I will even 
have to pay to get the valve cover put back on to drive it out of there 
if I don't want to pay them to change the engine.

At a loss.

--Art
<SNIP>
 
 
 
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.
 
First of all, each dealership handles these cases differently. Ours was more than happy to replace the engine given that the cam bearing surface was scored. If not, they would replace the oil pump and pickup tube, and anything else that might have needed it. Audi in no way recommends flushing the engine, but that doesn't mean you can't do it. 
 
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. 
 
Oh, and Audi only changes the oil when recommended, not before. That is why it wasn't changed at 18k.
 
I just wish you the best of luck,
Tony Hoffman



		
---------------------------------
 Start your day with Yahoo! - make it your home page