Using rear O2 as front: I popped a P0134 and P0154

[Supercharged111]

Just got some longtubes installed in the Z06 and they came with no cats. I'd heard of the F body guys rewiring rear O2s to work as fronts and I decided I liked that idea. Their idea was that they have more robust heaters out back. I welded in 2 O2 bungs in the new pipe in the factory location, so my wire routing is completely unchanged. That said, I haven't gotten the wideband installed yet and it does smell lean, and the car popped a P0135/154 which is insufficient switching. Could the distance from the engine have something to do with the switching? Or the fact that the new piping is 3" so now not only is the exhaust travelling farther to hit the "front" O2 sensors, it also travels slower? Not many people in the Corvette camp go this route, it seems to be more of a Camaro thing.

[picnic_george]

The F-Body guys use corvette rear o2 sensors because they are long and you don't have to use an o2 extension harness when switching to a long tube. Not actually rewiring anything, just pluging the sensors in to the primary sensor harness.

The rear corvette sensors are like 45" long and the front F-body sensors are something like 12 and 16 inches IIRC

[Supercharged111]

And those sensors don't cause the MIL to illuminate I assume? Here's where I have mine.



Since the car never threw a MIL before the swap, I wonder if they're too far back? Or has someone done what I did before?