Re: oil consumption...why?

[Wolff <wolff_b@ix.netcom.com>]

The difference is positive manifold pressure. How this would affect it,
I don't know. Especially since the turbos run most, well some,;-)  of
the time at less than atmospheric pressure. Sucktion past intake guides
and pistons?
Wolff

Andrew Duane USG/PE wrote:
> 
> Hairy green toads from Mars made C1J1Miller@aol.com say:
> 
> > I've heard that high oil consumption (over a quart every 3k miles) is common
> > on the 20-valve normally aspirated engines ('90-'91 coupe quattro, '91 90q);
> > however, from other sources, the 20-valve turbo engines ('91 200q, later
> > S4/S6) is not known for burning much (if any) oil.  I'm pretty sure the valve
> > guides, etc. are the same between the two engines (and probably other
> > 5-cylinder engines); so what is the likely cause of the oil loss?  Any
> > comments?  Comments about possible bullet holes through the block specifically
> > _not_ encouraged...
> 
> I don't know engine internals, but Angela's 90Q20V needs at least
> a quart, sometimes two between 3000 mile oil changes. My 100Q10V
> needs nary a drop (it is down maybe 1/2 quart by 3000 miles).
> 
> Every mechanic I have ever talked to said this is "normal"
> for the NA 20V engine. I think even Bentley/Alldata says it.
> 
> --
> 
> Andrew L. Duane (JOT-7)                 duane@zk3.dec.com
> Compaq Computer Corporation             (603)-884-1294
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