Open loop - closed loop

["Eric H." <ejham@domain.elided>]

And after all I thought I knew...

My GTV6 has been spitting and sputtering more than usual lately. For
the first time, I checked it out in what I believe is 'open loop'
mode -- short the full-throttle switch leads together, correct? (it
never pays to assume you're right...that's why I'm asking. Can someone
assure me that my assumption is correct?) Anyway, I suddenly had a
totally different and much higher performing car. This simple act did
added low-end power and an end to any 'bogging.' It also added a new
scent to my exhaust which told me that I was burning rich and would
probably pass no emissions tests -- fine for now...but this will burn
my cat and prove problematic at testing next January.

So my main question is this: How do you enrich an L-Jectronic system
across the throttle range? Idle I understand. But what about the rest?
The car has the heavy breathing Sperry Stage 3 heads and cams that may
or may not be stock. The recent stumbling and stuttering is probably a
by-product of a failing thermostat -- the car runs at 150 on the
highway...too low -- and more-or-less fine when the temp rises enough
to kick in the fans provided you drive it hard. But this open-loop
testing shows that if things run really rich the car has loads of low
end and fractional throttle power while enhancing it's over-4500 RPM
performance.

I will be doing some voltmeter testing on the new O2 sensor to see if
she is indeed running very lean while closed loop but not for a few
days. If I find that this is the case, how do I achieve a richer
mixture in closed loop? (The air mass sensor has been tampered with by
a PO...I've read that the gear/spring setting can affect mixture. I
also have an un-opened spare air mass sensor from my 73K mile parts
car.)

Advice, experiences, stories and tall tales appreciated.

- - Eric H., Clearwater, Florida (Florida -- home to once-a-year
emissions testing with no 'spot checks' or 'mobile detectors')

1983 GTV6 'Felicite' -- who seriously kicked two Maxima's behinds on
the way home from work today

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