I need a little help on this issue.   its my 87 samurai,  stock 1.3 8v carbed engine.     

after holding the rpms at 2-3k or so, when I let off the throttle, the idle drops to about 400rpm on the tach, and the engine sounds like it wants to die out.   

So far I've got fresh fuel, a clean carb, no obvious vacuum leaks/cracked hoses, and my motor is firing on all 4 cylinders.   I know its been sitting for 2-4 years, so I'm suspecting the fuel pump MAY be at fault, or a filter issue possibly. I'm unable to determine it 100% right now, but from my motorcycle experience, this acts like a fuel delivery issue.

can someone please shed a little light on this for me?   I'd GREATLY appreciate it so I can get my baby running well again.

also, to completely bleed brakes, is it best to have the engine running so the vacuum assist provides more pressure to push the air out?

did you try adjusting the idle on the carb?

the idle is set to 1000rpm, maybe 900,  so its not an idle adjustment.   

it clearly sounds like its not running right when it does this, like a fuel issue or something.

Maybe the EGR valve is hanging open?

I had the same problem and I ended up trashing the factory carb and going with a webber 34 it was the best move for me cause I did all you have already done plus new fuel pump, filter, vaccume hoses, egr valve, now I have one vaccume hose coming from the distributer and 1 12 volt wire going to the choke and Life is alot easier now!