Selinite

Hello, So I have an 04 Impreza 2.5 rs that I just bought a week ago and it started throwing codes, one was for the 02 sensors which was fix and the other was p0778 pressure control solenoid b electrical,also when my car got up to high rpms the AT temp light start flashing and the car would stop shifting..My friend replaced the Solenoids( he replace 2-4 break duty and 2-4 break timing) and the check engine light is now off. I took it for a test drive after he replaced the Solenoids.. and it was driving fine for a minute then I jumped on it and when the rpms got high again the AT temp light started flashing again and would do the same thing(but the CEL didn't not come back on this time) when I shut my car off and turn it back on the AT temp light goes off(sometimes it will come on when I first start my car and the car is idling) I am at a loss of what is wrong and so is he... is there anyone out there that might know what might be up thanks