Looking for help. After getting warm my 4runner drops from is cold start 1000 rpm to 600-500. And when I put it in gear it’s bogs down and misfires. I am doing a tune up but wanted to see what you all say.

 

Could well be the idle adjust screw o-ring.
Bear in mind, the idle adjust screw is under the cover screw. Big screw on top of the TB, front, left side as you look at it. Take the cover screw off, tighten the idle adjust screw in until it bottoms, counting the turns carefully, then unscrew it all the way out. There should be a small rubber o-ring on the bottom of the threads. Clean the channel it partially blocks to adjust the idle. If the passage get clogged up with ick, they can cause real trouble. A couple of shots of carb cleaner, using the little red tube they include should clean the passages pretty well. Wear eye protection, though. Backblast can be pretty rough, especially if they are clogged with stuff. The small o-ring is readily available in most auto parts, or hardware stores.
Put a thin layer of Vaseline, or silicone dielectric grease, on the o-ring before you install it. Then screw it all the way down, and back it out to where it was when you started. It's a starting point. From there, you can adjust it in or out to set the idle to 800-850 RPM.
Once the idle RPM is set properly, you can check/set the timing, and then verify the idle RPM again, just to be sure.

A shot of carb cleaner into each vacuum port on the TB can clean them out. A clogged vacuum port can cause trouble too, after all.

Have fun!
Pat☺

 

I'm curious to hear if the tune up helped. Weak spark due to worn plugs, wires, or distributor components can cause misfires at low idle as well.