I just bought a mustang GT, it's got the 4.6 motor, it came with an aftermarket intake on it and i am getting engine codes P0171 and P0174, I have changed the fuel filter, and cleaned the mass airflow sensor, i cleared the code afterwards and it keeps coming back. The car idles fine, it has a little hesitation when i floor it but other than that the car seems to run fine. Could the aftermarket intake be causing the code or am I just missing something all together? I'm on a budget so i am trying to get a better idea of what the problem is without changing 4 or 5 different things, any help would be greatly appreciated, thank you...