O2 pre/post cat interchangeable

[Most_Wanted]

Is there a difference in operation for the pre/post O2's? I know one measures A/F for the ECU and two monitors for cat efficiency. My question is are they interchangeable? I installed headers and the the primary O2 was barely long enough causing a tug on the wires. I noticed the wiring for the secondary O2's being slightly longer & would have swapped them but didn't want to chance it.

[Anker]

I suspect there isn't, but Pelican sells different parts for the two. I went with the Pelican recommendation. I also bought the tool for removing them.

[mikefocke]

Same except for the length of the pigtail. Bosch makes em. Use only ones with factory crimped pigtails. Do not use solder. An install any muffler shop can do. Mine took 15 minutes most waiting for a cool down.

[Gelbster]

If the problem is cable length(??) -simple just unhook the connector from it's clip on the cam cover.That will give more length. But be careful how you arrange an alternative restraint .Don;t want that connector flapping around while driving.
A bigger complication may be the need to fit extenders to the o2 bung to avoid a CEL

[particlewave]

Originally Posted by mikefocke

Same except for the length of the pigtail. Bosch makes em. Use only ones with factory crimped pigtails. Do not use solder. An install any muffler shop can do. Mine took 15 minutes most waiting for a cool down.

FYI: you CAN solder O2 wires. Just move about 2" down the wire (toward the sensor) and nick the insulation deep enough so that bare wire is exposed. This will allow reference air in.

The only reason you typically don't want to solder between the connector and sensor is because the sensor draws reference air through the tiny gaps between the wires and insulation. When you solder, the solder flows down the wire and fills these gaps, blocking air flow. Easily remedied by moving down the wire a bit and nicking the insulation.

The whole "increased electrical resistance of solder" thing is 100% myth. A crimp connector will have more resistance, especially when it starts to oxidize.

[Most_Wanted]

Good to know they function the same. I eventually got a recurring CEL(P1115). From what i read has to do with bank 1 pre O2 not heating at a specific time. Has happened twice. Always 5 minutes after restarting the car from a hour sit. I've researched but this CEL is hardly spoken of regarding headers. With the cats gone the O2 will take longer to warm but i have yet to pull a CEL from bank 2 and the engine still idles/runs fine. Will try swapping the O2 the next time i get under there.