Code P1171

[Ldub]

Forgive my waking this tired 'ol thread, but I'm having the EXACT same codes thrown at the moment.

P1171 - Fuel System Lean During Acceleration
P0157 - O2 Circuit Low Voltage (Bank 2 Sensor 2)
P0137 - O2 Circuit Low Voltage (Bank 1 Sensor 2)

My wrench swears up and down that he already replaced all the O2 sensors with brand new ones. He's at a loss. Therefore I am at a loss.

Snowtrooper, can you put please a ribbon on this one and tell us if and how you solved this set of codes?

Thanks,
-V

I'm fairly certain that those codes are indicative of unmetered air getting into the intake system, somewhere downstream of the MAF sensor.
Could be vacuum leak (hose or otherwise)
OR, vacuum leak (intake manifold gaskets)

Look HERE