Can ANYONE please help, over my head

Hello all

I am not sure this is the right forum but I sure hope you can all help. Today when I hooked my dyno scan to my 00 corolla my Maf was moving ALL over the place. In a split second it would reat .18lbs per min to 2.9 lbs per min and every # in between. I have an efie hoked to it and have for a while. I have been getting a trouble code P0171 for a while, even before I installed the efie and I fear my maf is dead. I cleaned it w maf spray, checked the connections, and checked it w the efie off all w out success. I know that it isnt giving me a true reading but my car doesnt and I can allready see myt MPG falling. Could this be brought on by adjusting the efie while driving? could it be somthing besides the maf causing the problem. I would love ANY input Many thanks Erik