So over the past 3ish weeks i have been putting a d16y5 in my 1990 civic hatch. i got the motor from a buddy who was selling his 91 crx. for some reason the car is throwing code 41 (oxygen sensor) and i also have a problem that when u slam on the gas the car just boggs out, seems like it falls over itself and then when u let of and push back down it catches up. what could be the problem??