Will overlap cause a false rich or false lean condition?
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Originally Posted by Robert56
What do you mean there is no contradication. One expert says it will add fuel and one says it will take fuel away. Other than that i believe what's been said is in agreement with what you say and proof is in sited work. False lean and adds or subtracts fuel? 
Endres is talking about a hypothetical, simplistic algorithm for pulsewidth calculation. He is defining a lookup table "B" as an adjustment to the base pulsewidth. In this hypothetical an increase in O2, in the exhaust, results in a fuel reduction via lookup table "B". This would result on an increased AFR.
Either he has created an inaccurate hypothetical example or he knows of a "special circumstance" lookup table ( one in which you would want to further lean out an AFR - above the measured AFR).
Regardless, this is not the normal functioning of a closed loop system. Normal is:
AFR above stoich -> add fuel.
AFR below stoich-> pull fuel.
As far as the O2 Sensors are concerned there is no such "False Lean". It's either lean or rich.
Target => Stoich
Bink, good insight. I think your right about Endres, as I tried to figure the math out in real world tuning and I was lost, couldn't figure it out. Furthermore, hypothetical alogrithm is maybe right on, until proven otherwise.
In conclusion, (like others said, but I have to know why) mongo overlap causes false lean (named because tune with normal cam would be allright?) and adds fuel accordingly, making idle problems even worse (compared to non pcm controlled set-ups). So, dump the maf and 02's and go into true SD mode with big cams?
In conclusion, (like others said, but I have to know why) mongo overlap causes false lean (named because tune with normal cam would be allright?) and adds fuel accordingly, making idle problems even worse (compared to non pcm controlled set-ups). So, dump the maf and 02's and go into true SD mode with big cams?
Last edited by Robert56; May 8, 2005 at 10:09 PM.
TECH Addict
Joined: Jul 2002
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Originally Posted by Robert56
So, dump the maf and 02's and go into true SD mode with big cams?
