You might just want to check all your clips on the variouse pipes that are on the air system to make sure no air leaks are occuring as well. including the PCV one as well that leads to the upper plenum.
Throttle body is easy clean, just make sure NOT to touch the butterfly valve when cleaning, get some carb cleaner or use wd40 like i did, 5 minute job.
Yeah mine was doing pretty much the same so I removed air feed pipe to throttle body cleaned the throttle and changed the air filter, had no issues since.