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more blue smoke

a buncha people wrote:
>> > << I was idleing
 >  for about 10 minutes before I actually got it inspected. When I got to
 >  the booth where they slap the sticker on, the guy pointed out the blue
 >  smoke eminating from my tailpipe, and then he paced I nice red failed
 >  sticker on my windshield. When I got home, after driving at highway
 >  speeds, the smoke was gone.
 >  Question: What could be causing it?
 >   Valves?
 >   Piston rings?   :-(
 >  Is anything common for these cars?
 >  It has 80k miles on it. 
 >  It looses about a quart of oil everything two thousand miles.
 >   >>

And I add to the babble:

I have rarely seen an audi engine in trouble at 80k (mine have gone 155k, 186k, 
and currently 107k,
and the first two were subsequently sold and are still in use)

Therefore, something is amiss, and you should not rule anything out.

Generally, if there is a weak link it is with the valve guides.  If bad enough, 
they will burn
oil after start-up, but that should have been proceeded by months of a puff of 
at start-up, which then grew worse.

Light oil?  Maybe.  In fact, light oil causes the problem.  Note that the 
manual warns against operation
at highway speeds or continuously with 5-30 oil at *any* temperature.  Over 20 
deg F they recommend 15W or
20W base number stocks.  10W40 is good only to 55 deg F, according to Audi.

This can be tested pretty easily be a good mechanic.  They can perform a "leak 
down" test to pinpoint
the cause.  Per someone's comments, do monitor it and insure that you didn't 
get puddling
at an innopportune time.

If your mechanic can't figure it out, or charges more than $100,  then the 
mechanic is also defective.

I doubt rings, unless you abused it cold (per Phil's comments some time earlier 
re: oval pistons, etc.)

One general note:  many people underestimate the value of treating a car gently 
until warm.  All parts
change size and shape as they warm up.  Until warm, the wear is 10-100x faster 
than when cold.  You can
basically do *anything* to a warm audi engine without problem.  Cold is another 
story, although I've
been lucky enough never to prove this through experimentation :-)