Cariboo4x4

Hey All. I have a code 32 and 44 with my 95 GMC Sierra 4x4. I replaced O2 sensor and egr valve. After an hour of regular driving to a few hours truck will suddenly or slowly start losing power. Sometimes so bad it will barely make small hil. The EGR solenoid seitch appears to be fine. So best remedy is to let truck sit turned off for 30 minutes, then it run awesome again anywhere from an hour to 4 hours or so. Codes 32 and 44 keep coming up. I’ll erase codes by taking main ign fuse out and sometimes not. Best remedy is engine off for 1/2 hour. I have new fuel pump and filter. I’m thinking TPS may be the problem. Its definitely not overheating. Anyone have similar problem?