Dirty intake manifold..

Pulling it to check valves and replace valve cover gasket.

There is a dirt/oil residue. Air filter was changed 6 months ago.

See pic:

 

That looks clean to me, there's always gona be some buildup in the intake because of the PCV system pulling oil vapors from the crankcase.

 

Looks clean compared to some I have seen.

 

That is exceptionally clean, all of that though is from the PCV valve functioning as it should, if anything it might be clogged given how clean your runners are so maybe it's time to replace the PCV.

If you want to get rid of that you would need an oil catch can but the benefits of are debated.

 

Dirty......are you crazy......I had to use 2 cans of oven cleaner and qt of awesome concentrate cleaner and half days work to get mine that clean.......
......but I had 160K of egr soot.....


And yep, they have inline oil catches, however the one that would work with tacoma pcv was right around a hundred dollar bill.....
.....and as stated, advantage is debatable......

Changing oil often is probably best you can do.....at least then its clean oil going thru pcv system......instead of nasty black.....

 

That's pretty clean man. I've seen them completely black, caked, and with brown stained carbon-colored-hues on the inside.

 

Also thats a good sign......You dont want those acid gases from blowback hanging out in top of your engine.
Burn baby burn..........another reason the toyotas last so long......