[s-cars] Really LOW Boost!

[Igor Kessel]

Calvin & Diana Craig wrote:
>
> OK guys, here's the problem.  I normally get about 15-20 psi depending upon
> the usual stuff, rpm, weather, load, etc.  Today I was getting this "normal"
> boost one second and the next time I stepped on it I got 4-5 psi, even too
> low for just wastegate spring level of boost.  All of a sudden.  No other
> symptoms...no missing, etc.  Revs smoothly to 7k rpms.
>
> I checked the hoses, lower intercooler hose was just recently
> replaced...they look fine.  On top of that I don't hear any of the
> horrendous whoosh noises that usually accompany leaky hoses.
>
> Swapped bypass valves with my '91 200...no difference.
>
> I examined the wastegate diaphragm and it looked OK.
>
> I removed the hose to the lower chamber of the wastegate which should cause
> boost to scream up until the fuel pump cutout, but no luck, it did make it
> up to 8-9 psi, though.
>
> This is obviously not computer related since all that was knocked out of the
> running with the last test I did.
>
> Are damaged turbos that all of a sudden lose 15psi of capability still
> capable of producing 8-9 psi?
>
> I am really struggling with this one.
>
> Thanks for any help!
>

Calvin,
somethign tells me it might be computer related after all. The limp-home
mode is about 5psi.

--
Igor Kessel
two turbo quattros