I would just plug the one in the downpipe and leave the 02 sensor in the cat. There should be a secondary O2 sensor in the back half of the cat...or at least a filled bung. Just use the one bung. The extras, I am assuming, are just there in case you want to run without an O2 sensor completely.

 

sounds good but it is still confusing me as to why in the directions it says to remove the o2 from the exhuast manifold. It is made for the 94-98 gsr do any of these years have a o2 in the ex manifold???? If not why would they put that in there but it doesnt ever say to hook the o2 into the downpipe nor does it say to plug it. It just kinda assumes the installer knows I got some other contacts that I can get ahold of tommorow but I bet what you said will be correct

 

and if I only have one o2 sensor wouldnt the obd2 pic that up and throw a check engine light? My car does have the obd2 since its a 96 right?

 

The instructions may just be very general and omitting the fact that the O2 sensor isn't in the manifold, but in the cat on 94-99 GSR's. They probably assume that if you can install the turbo, you can figure out what to do about the O2 sensor placement as well. I would say just leave the O2 sensor alone and plug that bung on the downpipe.

Yes, it would. Can you post some pictures of your cat to confirm that it isn't there?

 

I did find the posterior o2 so that puts me at 2 o2 sensors. So I should be able to plug the downpipe with the bung here are the pics so you can verify. Also I am changing over to the obd1 for tuning perposes along with a hondata. Can I run both o2 sensors with the obd1 or would it be better to run it with just 1???/

 

OBD1 doesn't even support a secondary O2 sensor, so just consider your secondary O2 sensor a plug to fill in that other bung. I don't even have my primary O2 sensor functional, it all runs in closed loop.

Just plug the downpipe and you are good to go. :thumbup: