Has anyone seen afr bank 1 go to zero for a second or two on datalogs using the SCT X4 and laptop? I was data logging my latest tune and all my knock sensor problems are gone. The only thing I notice is at low rpm when you accelerate by pushing down anywhere from 1/4 to 1/2 throttle I get a slight bog then t goes. I do not see any knock sensors going of but on one log I see it go to 0 on one of the banks. What should afr be at?
Could this just be a logging thing or a don't care? or do I have a bad 02 sensor?
Or is AFR 0 good ?
so according to wikepedia LOL..
2 is running rich.. and my value of 0 is lean
Air–fuel equivalence ratio (λ) [edit]
Air–fuel equivalence ratio, λ (lambda), is the ratio of actual AFR to stoichiometry for a given mixture. λ= 1.0 is at stoichiometry, rich mixtures λ < 1.0, and lean mixtures λ > 1.0.
There is a direct relationship between λ and AFR. To calculate AFR from a given λ, multiply the measured λ by the stoichiometric AFR for that fuel. Alternatively, to recover λ from an AFR, divide AFR by the stoichiometric AFR for that fuel. This last equation is often used as the definition of λ:
\lambda = \frac{AFR}{AFR_{stoich}}
Because the composition of common fuels varies seasonally, and because many modern vehicles can handle different fuels, when tuning, it makes more sense to talk about λ values rather than AFR.
Guess I answered my own question have to talk to my tuner to verify
Has anyone seen this big of a difference on their measured AFR's??
Could this just be a logging thing or a don't care? or do I have a bad 02 sensor?
Or is AFR 0 good ?
so according to wikepedia LOL..
2 is running rich.. and my value of 0 is lean
Air–fuel equivalence ratio (λ) [edit]
Air–fuel equivalence ratio, λ (lambda), is the ratio of actual AFR to stoichiometry for a given mixture. λ= 1.0 is at stoichiometry, rich mixtures λ < 1.0, and lean mixtures λ > 1.0.
There is a direct relationship between λ and AFR. To calculate AFR from a given λ, multiply the measured λ by the stoichiometric AFR for that fuel. Alternatively, to recover λ from an AFR, divide AFR by the stoichiometric AFR for that fuel. This last equation is often used as the definition of λ:
\lambda = \frac{AFR}{AFR_{stoich}}
Because the composition of common fuels varies seasonally, and because many modern vehicles can handle different fuels, when tuning, it makes more sense to talk about λ values rather than AFR.
Guess I answered my own question have to talk to my tuner to verify
Has anyone seen this big of a difference on their measured AFR's??
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