stalling and bad idle

i have a 1997 gmc sonoma 4.3 i just put a new egr valve in it while it is stopped and in gear with the defroster on or a/c when the compressor kicks on sometimes it will stall then when you go to take off it will sputter for about 3 seconds and go now that i put the new egr in the check engine light is off but it is still giving me the code p0171 system too lean bank 1 can somebody please help me

if its the voretech their is a idle controll valve on the top of the motor and it needs to be replaced it controlls how much air it gets at idle or it could be the coil