O2 sensors

[Dewayne]

I checked and I have 4 O2 sensors in the exhaust system on the truck.

The truck has a small CAT on each cyl. bank. There is an O2 sensor before and after each CAT.

I know if I install an EFIE it has to go to the one in front of the CAT.

Do I need an EFIE for each of the front O2 sensors?

[Kwiksilvr]

yes... you do...

[Dewayne]

Tks Kwik, now I have another question. I understand there are 2 types of O2 sensors. narrowband and wideband. How can I find out which type these are.

[timetowinarace]

When I get time I'll look it up but I believe narrowband has 2 wires and wide has three or more. I'm changing the sensor in my nissan right now and it just has one wire.

[daddyspaz]

Wide band is very uncommon. i dont think chevy ever used wide band.