stupid question for you guys: when making piggie pipes, why is the 02sensor relocation necessary to
12-29-2004, 10:38 PM
#1
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stupid question for you guys: when making piggie pipes, why is the 02sensor relocation necessary to
avoid a CEL? the sensor's original location is not after the precat, not in the precat, but before the precat. so how would the sensor know if the precat was there or not? thanks!
12-29-2004, 10:47 PM
#4
With O2-sensor-A before Cat#1 and the O2-sensor-B before Cat#2 ...
The ECU must derive Cat efficiency by comparing A with B.
Turbine -> O2-A -> CAT#1 -> O2-B -> CAT#2 -> Muffler
If Cat#1 is going to be removed then I think if you add a third bung after Cat#2. So that sensor-B can be relocated to after the Cat#2. Fill the second bung with a plug. Then the ECU will still read the differential across a Cat, albeit only Cat#2.
Turbine -> O2-A -> Nullified Cat#1 -> Bung-Plug -> CAT#2 -> New Bung O2-B -> Muffler
That should avoid the CEL.
Turbine -> O2-A -> CAT#1 -> O2-B -> CAT#2 -> Muffler
If Cat#1 is going to be removed then I think if you add a third bung after Cat#2. So that sensor-B can be relocated to after the Cat#2. Fill the second bung with a plug. Then the ECU will still read the differential across a Cat, albeit only Cat#2.
Turbine -> O2-A -> Nullified Cat#1 -> Bung-Plug -> CAT#2 -> New Bung O2-B -> Muffler
That should avoid the CEL.
12-29-2004, 11:03 PM
#6
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the 2nd o2 sensor is relocated to behind the main cat instead of in front of it.. ok, thank you! for
some reason, i was thinking the first sensor had to be relocated to behind the main cat.
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