Hey guys! I’m just a kind of beginner in switching engines. I had work on suspension and body work a little bit. So I have a 1996 ex with d16y7 engine that originally came with car as it was special edition that was made in canada only. So my d16y7 was not giving good mileage and it was automatic. Got a deal on marketplace for d16y8 engine with manual transmission off 1998 si(canada). So i swapped the engines with the harness that came off d16y8 and added manual pedals, shifter and everything and ecu from the same si car but car has cel for secondary o2 sensor but harness only has one plug for primary o2 sensor. My car has aftermarket exhaust headers. But after swapping the engines and starting the car, it runs rough. Idles is okay but car sounds like it trying hard to stay on. Also very loud, don’t know if i have exhaust leak as well from headers. So i’m not sure if i should drive it or not. I don’t want to take it out and and tow it after. Help me find why my car is sounding like this.