i recently purchased a 90 4runner with the v6 for next to nothing, saved it from the scrap yard, any way it had a bad knock that sounded like it was coming from under the valve covers. pulled the intake and covers but everything looked ok, when i put it back together it was still knocking but noticed at higher rpm it would quiet down and sometimes stop well when i started it up a few days later the knock was gone but now i have no oil pressure and it seems to want to die if you give it any throttle. my question is would it be in my best interest to take it to a mechanic and have them figure it out or just tear it apart and have it rebuilt. it has 220000 and i dont know how the previous owner was with maintenance. thanks in advance for any help it is greatly appreciated
