Well I have been having all kinds of problems with my yota lately. First thing, I threw the #3 rod bearing so it was then time for a rebuild. I went ahead and bought a new motor for the truck and sold the old one. I get the thing back together and I still have a CEL light. One was the o2 sensor code, so I replaced the sensor because I knew the old one was bad. Next I get a code 52 which is the knock sensor code. So I take the truck to a guy here in town that was recommended by some buddies, they say he is good with the yotas. He takes a look at my truck and tells me that I need 2 o2 sensors. Does this make sense?? The manifold I have in the truck is not original and it has an o2 sensor in the manifold. The problem is that I have no wire in the harness that has a coupler in it to hook up the o2 sensor. Second I found is that it does not have a knock sensor on the motor. I didnt have one on the old one either. So I look for a knock sensor wire and I cant find it anywhere!! no cut wires in the harness. I can feel the truck loose power soon as the CEL comes on and my fuel mileage is terrible. Im talkin about 12 MPG on a fresh motor. Does anyone have any suggestions or has anyone seen this problem before?? Any help would be awesome, I feel like I am chasing my tail here.:headbang: