Help us help you. By posting the year, make, model and engine near the beginning of your help request, followed by the symptoms (no start, high idle, misfire etc.) Along with any prevalent Diagnostic Trouble Codes, aka DTCs, other forum members will be able to help you get to a solution more quickly and easily!
Your MAF value is too low. Supposing you got the V6, 3.2 liter engine it should hover around12g/sec. The fact that both banks are affected in the same way may also point to a MAF issue.
Do you actually see any short term fuel trim other than 0 in any moment?
How are your fuel trims in other load and rpm ranges?
An expert is someone who knows each time more on each time less, until he finally knows absolutely everything about absolutely nothing.
