Indicated AFRs misbehaving
#1
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Indicated AFRs misbehaving
So, recently my AFRs have started behaving very sporadically, with no changes to my tune whatsoever. Before, WOT would get me mostly under 13:1, sometimes upwards around 13.2. N/A. Now, it's solid 15s/16s. It goes rich between gears and on decel (though this is probably just a lack of overrun)
Initially, since this all just suddenly started happening, I thought maybe my pre-cat (CA-spec car) had become clogged. I still think this may be a possibility, but I now have to helicoil a hole in my head due to the bolt bringing 2/3 of the threads with it, and I stopped swapping them there. I'll reapproach this idea when I have time.
Tune and Log attached. Ignore the AFR target table. It has been modified, but the VE table hasn't. Haven't run VEAL or enabled EGO since.
Suggestions?
Wideband issue?
Car is actually running at those AFRs?
Initially, since this all just suddenly started happening, I thought maybe my pre-cat (CA-spec car) had become clogged. I still think this may be a possibility, but I now have to helicoil a hole in my head due to the bolt bringing 2/3 of the threads with it, and I stopped swapping them there. I'll reapproach this idea when I have time.
Tune and Log attached. Ignore the AFR target table. It has been modified, but the VE table hasn't. Haven't run VEAL or enabled EGO since.
Suggestions?
Wideband issue?
Car is actually running at those AFRs?
#3
Boost Pope
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Disclaimer: I've never dealt with a clogged cat first-hand.
What makes you think this?
Having no actual experience in the matter, I would think that a plugged catalytic converter would manifest itself in the form of richer AFRs, not leaner. By restricting the exhaust flow, you're going to get less intake air for the same MAP. Less air with same amount of fuel = richer AFR.
Having no actual experience in the matter, I would think that a plugged catalytic converter would manifest itself in the form of richer AFRs, not leaner. By restricting the exhaust flow, you're going to get less intake air for the same MAP. Less air with same amount of fuel = richer AFR.
#4
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Disclaimer: I've never dealt with a clogged cat first-hand.
What makes you think this?
Having no actual experience in the matter, I would think that a plugged catalytic converter would manifest itself in the form of richer AFRs, not leaner. By restricting the exhaust flow, you're going to get less intake air for the same MAP. Less air with same amount of fuel = richer AFR.
What makes you think this?
Having no actual experience in the matter, I would think that a plugged catalytic converter would manifest itself in the form of richer AFRs, not leaner. By restricting the exhaust flow, you're going to get less intake air for the same MAP. Less air with same amount of fuel = richer AFR.
(EDIT: just adding for anyone not familiar with the cal-spec setup. This cat is part of the header, so the wideband is POST cat (well, after the first cat, before the second))
EDIT: the other was too big to upload here. https://www.dropbox.com/s/gtorfrt4ub...42.09.msl?dl=0
#7
Boost Pope
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Is this even a valid configuration? Running a wideband after the pre-cat? I mean, the factory NB02 sensor is before the first cat, I can't imagine how the readings wouldn't be distorted by placing a wideband after it.
[/voice of absolutely no experience whatsoever]
#8
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Ah- I missed that part, assumed you were running the wideband before the cat.
Is this even a valid configuration? Running a wideband after the pre-cat? I mean, the factory NB02 sensor is before the first cat, I can't imagine how the readings wouldn't be distorted by placing a wideband after it.
[/voice of absolutely no experience whatsoever]
Is this even a valid configuration? Running a wideband after the pre-cat? I mean, the factory NB02 sensor is before the first cat, I can't imagine how the readings wouldn't be distorted by placing a wideband after it.
[/voice of absolutely no experience whatsoever]
(Picture taken recently (in the past week))
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