You are right I do have it backwards (electronic dyslexia). Now the point
about the O2 sensor being switched off at full throttle is interesting.
.basically the black box must be nothing more than a fancy relay between
the switch and the sensor. Indirectly the fuel is enriched by  shutting
off the sensor, yes?

Still no explanation why there is not electricity flowing through the
switch as per Hayne's (would the sensor have to be activated ie above
300F-hmmmmm?)

I chose not to block the EGR valve but have experimented with both open
and closed modes and
found fuel consumption and head temp to be the same; still as you say its
disruption may have synergistic effects....DC 

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David Carment
School of International Affairs
Carleton University
Ottawa, Ontario
K1S 5B6
voice - (613) 788-2600-6662
fax - (613) 788-2889
Email address: dcarment@ccs.carleton.ca
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