Insane O2 Voltages?
Thread Starter
Teching In
Joined: Feb 2004
Posts: 9
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Insane O2 Voltages? Did a few initial logs today... Had some what seems to be weird results.
As soon as I go WOT my O2 voltages drop near 0 values (0.040v).
From what I gather these values during WOT should be in the .850 to .950 range.
I'm attaching a sample image of my logs.
Any help is greatly appreciated...
l
As soon as I go WOT my O2 voltages drop near 0 values (0.040v).
From what I gather these values during WOT should be in the .850 to .950 range.
I'm attaching a sample image of my logs.
Any help is greatly appreciated...
l
Last edited by ls1itr; Mar 18, 2005 at 11:06 PM.
It looks like you're misfueled, lean, in open loop. Why, is
the question. The O2s looked reasonably bouncy before.
You should log your fuel-air multiplier (which indicates the
intent), the LTFT pair, probably injector pulse widths so
you can post-process those for a duty cycle figure. The
O2s indicate it's well leaner than 14.7:1, is all. Not good.
But you have to get to the cause and that means collecting
more of the symptoms.
Anything like a nonstandard MAF in this picture? K&N filter?
Something has to be messing with either air measurement
(MAF at the big end, reading low) or fuel delivery (pump,
wiring, relay, lazy injector or your poor neglected fuel filter).
While you're at it, try some pulls logging misfire current 1-8
just on the chance that it -is- a lazy injector, a lazy spark
or some other source of excess exhaust oxygen.
the question. The O2s looked reasonably bouncy before.
You should log your fuel-air multiplier (which indicates the
intent), the LTFT pair, probably injector pulse widths so
you can post-process those for a duty cycle figure. The
O2s indicate it's well leaner than 14.7:1, is all. Not good.
But you have to get to the cause and that means collecting
more of the symptoms.
Anything like a nonstandard MAF in this picture? K&N filter?
Something has to be messing with either air measurement
(MAF at the big end, reading low) or fuel delivery (pump,
wiring, relay, lazy injector or your poor neglected fuel filter).
While you're at it, try some pulls logging misfire current 1-8
just on the chance that it -is- a lazy injector, a lazy spark
or some other source of excess exhaust oxygen.
Thread Starter
Teching In
Joined: Feb 2004
Posts: 9
Likes: 0
Thanks for the reply, I do have a Holley Powershot filter. MAF is standard, fuel filter recently changed. I'll do some more logging as you suggested.
I had LTFT's and Inject Duty cycle logged, LTFT were 6% and both injector duty cycles topped out at 65% @ 5200rpms.
Perhaps it would be worthwhile to switch out to a paper filter and clean the MAF wires in case they got coated in filter oil...
Thanks again.
I had LTFT's and Inject Duty cycle logged, LTFT were 6% and both injector duty cycles topped out at 65% @ 5200rpms.
Perhaps it would be worthwhile to switch out to a paper filter and clean the MAF wires in case they got coated in filter oil...
Thanks again.
Last edited by ls1itr; Mar 19, 2005 at 07:51 PM.
