99 integra ls issues

[mirving ls1]

ok so i got a 99 inteegra theft recovery a few months back and its mostly togeather it poped code after code and just wont run right it lacks power im poping 4 codes now 2nd o2 sensor high circet output cuz i got the wrong exhaust on it so i can fix that but would it cause my car to misfie on 2 and 4 and pop a random misfire ? there are no other codes i got new plugs wires cap and rotor tested the coil in the dizzy have right ecu the car is obd2 and the motor worked fine in a obd1 civic idk whats going on any ideas ???

[LS/Vtec]

is it a obd1 motor? Do you have a CKF sensor hooked up? Or did you bypass it?