02 Toyota Camry idles low sometimes?

[Just me]

My 02 4-cyl Camry has about 85K miles and has started idling low (200-400rpm) but only sometimes! It's not tied to the engine being warm or cold. Seems hit or miss, but when it's bad the engine will even cut off unless I goose it to keep it going. And when I do give it gas in this condition, there is a slight hesitation almost like the old days when you could flood an engine, as if if I stepped on the gas hard, I would flood it, so I have to gingerly goose it, give it a half second to catch, then push it.

I don't think it's a tune up issue since it's only sometimes. I'm trying to narrow down the possibilities before I take it to the dealer to prevent myself hundreds of dollars of needless repair.

Thanks!