My sons 99 GS has thrown a few codes: Your advice would be greatly appreciated.

P1767 & P0700 which are related codes: I am looking to start with the simple stuff so I want to change the EATX Relay. I can not find this relay anywhere online - the part # I got off the relay itself is this 04687146A 68832 2308. Is this a special relay? Is there any trick to changing it out? I removed the bracket with all three relays on it and it looks like it is clipped on somehow.

P0551 - Power steering pressure sensor switch. Not sure how to fix this? I pulled the hose off the unit and cleaned it up a bit as it looked dirty, the hose also has a bit of a kink in it so maybe that is what is causing the code to be thrown.

P0141 - Not really worried about this one yet as it is the rear O2 sensor.

Car seems to run fine but these codes keep popping up and I want to make them go away.

Thanks in advance.