help me please!

93 civic hatch w/ gsr swap running uberdata tuned by myself, basic mods, but no fuel upgrades. i have PLX wideband O2 permanantly in the car replaceing the stock o2 sensor.

i live in florida, and it seems like as soon as it started gettin hot this summer, the car started having problems... it will randomly lean out while driving, sometimes when its low on gas it wont start at especially if the engine isnt compleatly cold. when it does this it will initially start up, but then fail to catch an idle and just die right out, even if i give it gas, repeated attempts to start prove to just make it die quicker. it will eventually work after i let it sit for a day or so. when it will run it will lean way out at idle and almost stall, keeping just enough to stay alive. all of these problems seem to be most evident when its hot outside, little to no problems at night. i would almost think its just a problem with the idle settings, except for the leaning out while driving... and that the bad idle seems to be because it gets so leaned out (my PLX actually goes off the chart and just reads "LEAN" or "AIR")

so it seems to me like either its bad tuning with the uberdata on my part (it is running closed loop though, so i dont think my tuning has much effect on idle or everyday driving) or the fuel system is having trouble holding up to the fuel demands of the GSR (the fuel system is from the stock civic Si and has 135k miles on it) but i dont know the symptoms of a fuel system having trouble, i just know that it is a possible problem area with the swap.

thanks in advance for any help! you guys are the best.