[200q20v] speedo and boost,....Foggy windows.

[Phil Rose]

At 11:00 AM -0400 9/28/2000, Brian.Link at Level3.com wrote:
>Well I finally got time to install my boost gauge on the A-pillar using a
>VDO vision series gauge and a A-pillar Gauge pod designed for an Acura
>Legend.  Well the fit wasn't that close, but the heat gun can turn the
>plastic into putty for easy molding, that and a dremel.
>
>I could use some help on a few issues.
>the car is a 91 200tq with a tap modified computer.
>
>1. I have had a surging problem at high boost and I'm trying to fix it.
>With the boost gauge I can see the needle go up to 19 psi, then it
>oscillates (really quickly) back and forth from 14-19 psi.  any guesses?
>Pressure leaks?,  WGFV?, ECU?.

My '91 200q has the group-purchase Anderson/Hoppen stage "sumpin' or other"
mod with 2.5 bar transducer. The WG spring is stock (and untweaked). I'm
using a cheap JC Whitney boost gauge (T-ed near the ECU), and I see the
boost climb smoothly to about 17+ psi and then oscillate rapidly over the
16-18 psi range. Definitely does not drop as low as 14 psi (nor does it
ever reach 19 psi). I've assumed this oscillation is the action of the
WGFV, and it seemed about "right". I'd be concerned too, to if I saw a 5
psi fluctuation.

How old is the WGFV? Mine failed completely just before sending the ecu for
chipping. It didn't give any obvious (to me) warning signs before failing
completely--at which point it caused a 1.4 bar default. However, during the
previous year or two, it may have been the reason that my LCD (oem) boost
gauge seemed to display very unreproducible values for max boost (1.5-1.7
bar). Now, with a new WGFV, the mechanical gauge response is very
reproducible (and so is the reading of the meaningless LCD gauge). So I
wonder: can the WGFV undergo _gradual_ failure, rather than be limited to
either "perfect" or "dead"?

Phil

*********************************
*  Phil & Judy Rose           Rochester, NY  *
*        mailto:pjrose at frontiernet.net       *
*********************************