u/Free_Patience_7910

I got a 1990 f-150 5.0. I've had these codes since I purchased the truck in March. The EGR and position sensor were pretty shot so I've replaced those, in addition to the solenoid, vacuum hoses and vacc tested the soup can. Everything seems to be working accordingly but the code 34 remains even after clearing it by disconnecting the ground to the battery for ~6 minutes. I've heard that aftermarket position sensors may need to be calibrated but I don't know how to check that and or how to tell if that is the issue. Any help is super appreciated thanks!

update: I've just checked my codes again and my code 81 is gone now, I assume from getting my vacuum lines routed correctly, now all that remains is 34..