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'83 ur-coupe "flatteneing out"...


This is to the guy who sent the posting about the '83 ur-q that flattens
out around 5200 rpm.

First, don't use the word "s*bscribe" in your posting. If you do, your post
will never reach us. Long story.

I'm going to assume that you have checked for all the obvious things - making
sure the air flow sensor plate moves freely throughout its range, no blockage
in the intake or exhaust system (is your cat clogged? Is the plenum-to-turbo
hose in good shape? Is the turbo-to-intercooler hose in good shape?).

Check your idle and full throttle switches. I suspect that you have the
connections switched, and that both switches are flaky anyway. With the
switches reversed, your full-throttle switch is clicked at idle. This puts
the car in open loop hence the non-fluctuating duty cycle (I'm assuming you
are measuring it at idle). But since this switch is flaky, sometimes it
doesn't make contact when it is clicked, so sometimes the car goes into
closed loop. When you wind the engine out, the full-throttle switch is 
unclicked so you never get full-throttle enrichment. However, at full
throttle, this would click the idle switch and cut your fuel pump at 4000
rpm. Since this isn't happening, it would seem that this switch is flaky
too, or not connected.

Check this first. If this isn't it, we'll keep looking.

*            Bryan Gunn                  Email: bgunn@voicetek.com           * 
*            Voicetek Corporation          Tel: 508.250.7998                 *
*            19 Alpha Road                 Fax: 508.250.9378                 *
*            Chelmsford, MA  01824                                           *