My dad is looking for the diagnostic port on his 1986 4Runner. Can anyone please help?

Facing the engine from in front of the vehicle there will be a "white plug" towards the left side of the engine near the plenum where you have to use a test wire to. This model does not have a ADL to plug into. This type requires you to count the blining check engine light while you have the test lead in to see what the code is.