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Re: Boost/vacuum numbers...

   While riding in my friend's '88 5000tq, I noticed that when he let up on
   the throttle, the boost guage would go down to 0.1 bar; sometimes he
   says that he can get to 0.0 bar on a long hill.  In my '91 200tq20v,
   I only get down to 0.4 bar (maybe 0.3 sometimes), but never that low.

0.0Bar is damn hard to produce in a laboratory. His gauge lies big time.

I typically see about 20InHg vacuum on decel, occasionally peaking in
the 25InHg region, on a fresh engine, all new hoses/etc, expensive and
accurate gauge.

   Do I have a vacuum leak somewhere?  No obvious driveability problems I
   can see or feel.  Any ideas of what to check for?  Or is there no

I would think you should see well less than .4Bar, but if you average
out lying gauges/sensors, you get .2 bar, which is in the right range.
In a '91, your hoses shouldn't have rotted out yet (unless Audi has
switched to new high-tech accelerated-rotting hosing), so you're pro-
bably OK. If your idle is stable, and starting is not a problem, then
I wouldn't try to fix it, you'll only break something.