Making Boost, but down on Power

Peter Schulz peschulz at
Thu Nov 20 15:12:18 EST 2003


Code corruption is NOT the likely culprit.

You need to be very explicit in what you have replaced.

Are there any codes?  Has your mileage decreased?
Does disconnecting the MFTS improve boost?

Have you done a pressure test of the boost hoses and IC?

This is all part of diagnosing the issue....


'At 07:13 AM 11/20/2003 -0500, Tom Daily wrote:
>Below is an e-mail I sent to Ned Ritchie the other day & have not heard back yet. Any opinions on what might be the problem? I guess I should do a compression check (?)
>Hi Ned:
>You've helped me before, I have a '91 Stage 3 modified TQ that you did through Kevin of Randolph Racing.
>Car runs fine, makes 19lbs. boost (manual boost gauge), but it is down on power--was 286HP on the G-Tech right after you modified it (had 70K miles then) now 195HP on the G-Tech with 113K miles. Have replaced all the usual suspects in valves, hoses, etc.
>Is it possible that your programming somehow got corrupted?
>Any suggestions would be appreciated.
>Many thanks,
>Tom Daily
>Boston, MA

Peter Schulz
1990 CQ (awaiting S2 3b engine transplant)
1991 200 20v TQW indigo mica
1991 200 20v TQW titanium grey 
Chelmsford, MA USA
peter at

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