Question for Rufus
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Question for Rufus
OK.
I wish to learn a bit on HOW the O2 feedback system works.
06-08. Lets start there. A Nernst cell O2 MAKES its own voltage. 450mv is Stoich/14.7AFR, right?
So, In MY mind... the O2 is a simple 2 wire, with one wire being the reference wire and the other being the return from the O2. And... as the O2 changes, so does the voltage on the output wire. Lean 200mv. Rich 800mv, etc. Right? So, then how does the CLB offset work? In MY mind, I always thought that the reference wire had some voltage placed upon it and the O2 sensor added to it. How else are we able to 'drive' an O2 beyond its means? I guess that could be done from the output side as well. This IS DC voltage (0-1vdc) and THINK voltages can be added, just like 2-12vdc batteries outputting 24vdc when in series, right? We drive the second battery to 24vdc simply by applying 12v to the negative terminal.
So, if we add in 200mv on the reference wire to both O2s, NOW the 450 is added in and the ECM 'sees' 650, all the time the O2 is still 'saying' 450... 450...450... right? (but by us adding that 200mv in the system... we ARE driving that O2 further to its edge of 800mv, right?)
I THINK I am correct on this but await an answer before I ask the REAL question (dealing with 09 up sensors). I want to be sure my thoughts are correct before I go further.
TIA
I wish to learn a bit on HOW the O2 feedback system works.
06-08. Lets start there. A Nernst cell O2 MAKES its own voltage. 450mv is Stoich/14.7AFR, right?
So, In MY mind... the O2 is a simple 2 wire, with one wire being the reference wire and the other being the return from the O2. And... as the O2 changes, so does the voltage on the output wire. Lean 200mv. Rich 800mv, etc. Right? So, then how does the CLB offset work? In MY mind, I always thought that the reference wire had some voltage placed upon it and the O2 sensor added to it. How else are we able to 'drive' an O2 beyond its means? I guess that could be done from the output side as well. This IS DC voltage (0-1vdc) and THINK voltages can be added, just like 2-12vdc batteries outputting 24vdc when in series, right? We drive the second battery to 24vdc simply by applying 12v to the negative terminal.
So, if we add in 200mv on the reference wire to both O2s, NOW the 450 is added in and the ECM 'sees' 650, all the time the O2 is still 'saying' 450... 450...450... right? (but by us adding that 200mv in the system... we ARE driving that O2 further to its edge of 800mv, right?)
I THINK I am correct on this but await an answer before I ask the REAL question (dealing with 09 up sensors). I want to be sure my thoughts are correct before I go further.
TIA
Last edited by wurk_truk; Jul 23, 2011 at 01:57 PM.
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