Ok...so you've bought yourself a Wideband O2 sensor....
and you get it all hooked up....
and you suddenly realize that something isnt quite right....
and you realize that you have an offset voltage....
so what do you do...
well..this is the "How to"
For this example I will use an LC1 because thats what I use
For Reference The Formula itself is
Volts/ [(0~Max Voltage)/(max AFR - Min AFR)] + [min AFR +any offsets in AFR values]
First lets start with setting up your Wideband itself
there should be some sort of way to program it or it should come with a set of instructions telling you what its AFR range should be and What its Voltage Range should be
I like to set things to be
0v=10AFR
5v=18AFR
this makes our Formula for HPTuners
volts/0.625 + 10
in this diagram we also see that our 14.7 crossing point(which can also be mathematically figured) is 2.95 volts
so next step is to set our outputs to = 2.95 volts so we can connect to the scanner and find out what offsets we have if any at all.
in our scanner we need to set up a histogram so that we can check our offsets.
basically like this is what I use
Custom Aux Input PID
Custom Histogram
thenwe can see what our actual readin is with an average over the course or several seconds...and its our actual reading in HPT Scanner as well..
if you see anything other than 14.7 then you need to adjust your formula slightly
as an example
if you saw an average of 14.5 then you woule need to shift your minimum AFR by 0.2
so the new formula would be
volts/0.625 + 10.2
if you saw 14.9 then it would be the other direction
volts/0.625 + 9.8
we never change our actual steps calculation (0.625 figured from 5volts range/8AFR range)
then once we have our scanner showing 14.7 we set our wideband back to the
0v=10AFR
5v=18AFR
and then we are ready to start tuning
for those that say their wideband is set up to do 5 volts and its only outputting 4.8 volts or something like that...dont worry about it
your calculation internally is still set up to take the same size steps...in our example 0.625
most of our "cheap/budget" widebands cant really output their extreme end voltages properly...meaning it cant really output 0volts(a dead short) and it cany really output 5volts(its extreme max)
internally it gets truncated when it hits the physical limits
the stuff in the middle is still correct and still moving at the same step size determined by the physical math of the calculation
also on some devices when you input a value it my get truncated to the nearest hexidecimal value internally...
on the LC1 it equates to 18AFR turning into 17.99..not enough to make any real difference...its not rocket science....yet...
Originally Posted by INTHERED