2000 gts sputters n stalls after refuel n high RPMs

I have a 2000 toyota celica gts 6 speed manual n it is havin all sorts of issues...my boyfriend n I just got done takin off the IACV n TB n cleaned both with carb cleaner... N cleaned the aftermarket Air Filter...at first it overheated (at least the gauge registered hot) but the engine was cool...so in unplugged the battery n let it sit over nite...after 2 days the CEL came back on n it's throwing a diff code at me...solenoid or small leak?? But it ran like a champ for 3 more days...Now today is a new issue!! When I fill my tank with gas an also when I am getting ready to shift gears the car want to spitter n stall...after I refuel it will sputter for about 2-3 minutes then it runs great...And after I shift through the gears it will run smooth n idle perfect...I'm now wondering if it's my MAP censor or even as simple as my fuel filter...anyone have any suggestions...please help a girl out! I love this car!!