P0505 is the IACV Valve. Are you having Idling issues (jumpy idle, etc)? If so, remove the IACV, clean the screen with Carb Cleaner and reinstall. Remove battery terminal for 15 secs, reconnect and start the car, the issue should be fixed. If you do not have Idling Issues make sure its connected properly. Also, before removing it and cleaning it first try clearing the Code and see if it comes back.
PO325 is the Knock Sensor. The JDM D15B Motor does not have a Knock Sensor, but your ECU (P2P) is looking for it as the Old D16Y8 Motor did have a Knock Sensor. You will have to live with this one, as there is not much you can do here. However, I've heard that some people have bypassed the Knock Sensor CEL Light by just connecting the Knock Sensor from the D16Y8 Motor to the Engine Harness Plug and securing it to the Block or Ground. Try that and see if that solves your CEL Light.
P1337 is the Crankshaft Speed Fluctuation Sensor (CSF or CKF). You need to make sure its working properly. Below are the procedures for testing this sensor and making sure it works correctly, you will need a Digital Multimeter (DMM). Before you do all those steps though, try clearing the Code and see if it comes back. If you swapped the Oil Pump and it was working fine before then it should not come back, but it might've gotten damaged, so if it comes back try the steps below to troubleshoot ...
- Set the DMM to Ohms and check for resistance between Pins 1 and Pins 3 of the CSF Sensor. It should read between 1.6k Ohms to 3.2k Ohms, if its not that then replace the Sensor.
- Set the DMM to Volts and check for Ground. One end to the CFK Sensor Pin 1 and the other to Chassis Ground. Then check from the CFK Sensor Pin 3 to Chassis Ground. Both times it should be open, if there is continuity, then replace the Sensor.
- Set the DMM to Ohms again and measure the resistance between C1 and C11 on the ECU Harness Side (Passenger Side Kick Panel). If there isn't 1.6k Ohms to 3.2k Ohms then there is an Open wire somewhere and you need to fix it.
- Lastly, set the DMM to Volts and check for Ground. One end to C1on the ECU Harness Side and the other end to Chassis Ground. If there is continuity then there's a short somewhere and it should be fixed.
Good luck and keep us posted!
- Danny