[s-cars] New stumble.....Altitude related?

[Wayne Dohnal]

>After 6 months of fairly trouble-free motoring at WOT and plenty of trips 
>all over the west, I happened on a WOT stumble last week here in the 
>mountains (7500 ft. elev.) of Colorado.

I frequently go over the Cascades and have had the same type of 
high-altitude stumble for a few years.  I've also started getting it 
occasionally at low altitudes.  I recently noticed three things about it: 
(1) It happens at almost exactly 5 psi of boost, and (2) If I shut the 
engine down and restart it, it goes away and stays away as long as the 
engine isn't shut down again, (3) It happens more often when I restart the 
engine after it being off for a few minutes, as in making a quick stop 
somewhere.

Wayne
1994 S4