Where exactlly was the O2 sensor located on the original set-up on 2.8L 91' Trooper. I just finished my 3.4L swap and all worked out very well, except that I used original exhaust manifolds that came with my 95' Camaro engine. So now I have three O2 sensors to choose from, one on each exhaust manifold and the original one down stream on pipe it self. I'd like to know because my original exhaust set-up looks nothing like the stock one and so I think that the sensor has been moved and not necessarily to the right spot.

Good judgement comes from a lot of experience and a lot of that comes from Bad judgement

3.4L 91' Trooper
4.3 TBI, Airmax 1" TB spacer