Nissan Repair: 1998 Nissan Maxima Knock Sensor, maxima knock sensor, nissan maxima knock sensor

Question
Von, sometime back i got your advice on removing the rear timing cover to repair a awful oil leak following the instructions the Haynes repair manual. I paid close attention to the timing instructions. when i completed the repairs and was ready for staring the engines it started with one crank. I drove the car around on numerous day to assure all is well with the engine. At one point I heard what sounds like a pinging sound that I thought would go away. At times after driving the car for sometime and restarting it the engine on starting it would drag a bit. I gave the car to a friend who also is a mechanic to connect the A/C lines. When he return the vehicle he stated the timing was off. This is where my concern comes in and I need the advice from the best. I am of the opinion that if the timing is off the dragging during starting should have started at the first time I started the engine after repairing the timing cover leak and it would always continue. My wife bought a hand held Actron OBD 11 scan tool from advance auto for me. I connected it and I saw the screen gave the following (2codes -P0325, Monitors,5incomplete- catalyst,evap,02sensor,02heater,EGR also is said 3ready-misfire, fuel and compressor. I need your help in explaining what to do. I know (p0325) is for the knock sensor, the compressor is not fully installed,the catalyst converter is not attached,the coil in the front nearest to the battery was broken at the top but it fitted in place and I applied CRAZY glue. Please  help as I said before this was a stolen car a put back together and i want it to be perfect before I give it to my wife. Thanks in advance.

Answer
Kingsley,

THe P0325 is the knock sensor.  And, this can be the cause of the hard start and pinging.  Replace the sensor.  The convert code is due to no converter being on the car.  Replace the converter so the rear oxygen sensor reads that the car has a cat.  Check the wires to the oxygen sensors and make sure none are broken since the one code refers to a bad oxygen sensor heater circuit.  The EGR is probably dirty and needs to be removed and cleaned.  After you do all of this reset the codes and drive the car around the block, turn it off and repeat three times to get the system into normal operation mode.  Email me back if you need more.