Chevrolet: 1996 impala ss check engine light, mass air flow, granatelli motorsports

Question
my check engine light was on and not going off went to a chevy store and they did nt fix it. i started changing hoses for pvc,breather any vacuum hose coming off the manifold. the light went out and stade out for a while now it comes on and off every week or two and then will goes out again. i had a scanner on it a few time and the same codes keep coming up bank 1 and2 running lean i think its code 173 and 175. sometime it comes up with 101 which i believe is the mass air flow. I have a granatelli motorsports mass air flow and took it out today and cleaned it. the car always seems to run just fine but that light just drives me nuts. Please Help, and thanks in advance for your help.                      Bill D

Answer
P0171 System Too Lean - Bank No. 1.
P0172 System Too Rich - Bank No. 1.
P0174 System Too Lean - Bank No. 2.
P0175 System Too Rich - Bank No. 2.

If you are getting any of those codes it could be that the MAF is bad or the O2 sensors are bad. If you still have the stock MAF, swap it back in and see what happens. Even though Granatelli is a reputable name, its still and electrical part that has a finite life and it will go bad at some point.