I have a Nissan 200sx ser with 230,000 Miles and my check engine light kicked on this morning. I went to autozone to pull the codes and this is what I got... P0325, P0402, P0136. I just replaced the knock sensor maybe a month ago after i got engine code P 0325, so i know what that one is. Last time my mechanic checked out the car after replacing the knock sensor he said the engine had some rattle to it and it could flip the knock sensor off again. While I'm out driving I don't notice any excessive vibration or loss of power like I did when the knock sensor was actually bad. I also don't hear or smell anything strange inside or outside the car so I'm not really sure what to do with these codes. What would you guys recommend i do to fix these issues because I'm drawing a blank on what could be the cause of this now.