Anyone know how to read the rear o2 sensor on MY01/02 yet?
Matt
Rear O2 voltage will work the same way as O2 voltage on the MY00.
The only thing you have to remember is that the gas is catted (unless you've removed them) and this will scale the values a bit.
The front O2 sensor has a much higher range.
Rear O2 voltage will work the same way as O2 voltage on the MY00.
The only thing you have to remember is that the gas is catted (unless you've removed them) and this will scale the values a bit.
The front O2 sensor has a much higher range.
Pete,
Well I've logged several MY01/02 WRX/STi's with and without CATs and the values output by the rear LS all seem to be way above the values put out by the <MY00.
So are you saying that if there is a Cat upstream of the LS then the voltage will be higher? If so, do you know what voltage = what fueling in say a standard car's case? Is the rear LS just upstream of the centre Cat (which would make it's presence irrelevant? ) or downstream (in which case it would effect it?).
I'll re-check the traces I've got though....
Cheers,
Matt
Well I've logged several MY01/02 WRX/STi's with and without CATs and the values output by the rear LS all seem to be way above the values put out by the <MY00.
So are you saying that if there is a Cat upstream of the LS then the voltage will be higher? If so, do you know what voltage = what fueling in say a standard car's case? Is the rear LS just upstream of the centre Cat (which would make it's presence irrelevant? ) or downstream (in which case it would effect it?).
I'll re-check the traces I've got though....
Cheers,
Matt
OK,
Had a look at some traces, all on boost:
JDM STi MY01 Full de-cat inc U/P = 0.96-0.98v
UK WRX MY01 Full de-cat inc U/P + PPP = 1v

UK STi MY02 Full de-cat inc U/P = 0.99v
UK STi MY02 SS Centre & BB (hot(ish) LS) = 0.94v
UK STi MY02 standard = 0.95v
So, Pete, I'm still confused because if there are no Cats, and it's the same sensor, going by the old sensor readings:
0.860v = 6% CO
0.880v = 8% CO
0.900v = >10% CO
...this would imply that the new cars are running at something like 12-15% CO which I don't believe for a minute.....something doesn't add up....

Matt.
Had a look at some traces, all on boost:
JDM STi MY01 Full de-cat inc U/P = 0.96-0.98v
UK WRX MY01 Full de-cat inc U/P + PPP = 1v


UK STi MY02 Full de-cat inc U/P = 0.99v
UK STi MY02 SS Centre & BB (hot(ish) LS) = 0.94v
UK STi MY02 standard = 0.95v
So, Pete, I'm still confused because if there are no Cats, and it's the same sensor, going by the old sensor readings:
0.860v = 6% CO
0.880v = 8% CO
0.900v = >10% CO
...this would imply that the new cars are running at something like 12-15% CO which I don't believe for a minute.....something doesn't add up....


Matt.
Matt
I've only measured using a volt meter, when developing the O2 fix.
The values were lower than you are seeing, but this was on WRXs. It was a while ago and I haven't got the exact numbers to hand, but we used to see a max of around 0.9v.
I've only measured using a volt meter, when developing the O2 fix.
The values were lower than you are seeing, but this was on WRXs. It was a while ago and I haven't got the exact numbers to hand, but we used to see a max of around 0.9v.
The US WRX guys seem to see about 100mV higher than the MY99/00. I never found a table to give any decent numbers. You could always RR gas analyse it and see and tell us all
Or ask PE to in the interests of them mapping the WRX and STi
Or ask PE to in the interests of them mapping the WRX and STi
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