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Closed Loop......Why?

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Old 03-08-2006, 07:20 PM
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Post Closed Loop......Why?

Finally had a bit of a chance to actually use EFILive on my car for the first time in months (yes, that is pretty sad!).

I have been running semi-closed loop since the last tune went in and everything has been fine. Now, I just switched back to full open loop mode to test something. There has been countless hours of logging to get my VE table spot on at idle - mid throttle, and sure enough it is all hovering just around 14.7:1 as expected, in fact, sometimes I wonder if the PLX is working it is so steady!.
So, this made me think, why should we even enable the O2 sensor STFT if the VE table is dialed in so accurate?


thank you
navy
Old 03-08-2006, 07:40 PM
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to accomidate changes in operating conditions.

Ryan
Old 03-08-2006, 08:37 PM
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No kidding.. especially if speeddensity.
Old 03-09-2006, 08:17 AM
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Mine stays in open loop all the time, and I've never had any concerns with it. I monitor my AFR with my XD-1 digital gauge all the time, so I know what it is doing at all times.
Old 03-09-2006, 12:35 PM
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The real reason for closed loop is that cats can't scrub
off the level of nasties produced far away from stoich,
and especially if -on average- the mixture and output
spooge are biased in one direction instead of producing
a soup that can supply both oxidation and reduction
"chunks" as it swings both sides of center.

That's why you don't see lean cruise, or "lean burn"
motors anymore despite that it would help economy.
Catalysts only facilitate reactions, they do not
consume anything and the reagents must be supplied
in balance, to get null output.




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