Fuel Pressure

[obadran]

I've got a 96 yukon 5.7L with a little over 100,000. I connected a fuel pressure gauge to the fuel rail a got a reading around 52psi with the engine ignition on but not running. I started the engine and the fuel pressure stayed about the same. With the fuel gauge still connected, I drove around the block and performed a few quick pushes of the pedal to the floor. The fuel pressure increased to near 60 psi and dropped back to around 52 psi once I let off the gas.
According to the shop manual, the pressure should be around 60-66psi with engine ignition on but not running and once the engine is running it should be between 3-10psi. I'm going to assume I have something wrong unless there is a missprint in the manual.

I have been having problems with hesitation and a general lack of accelaration power and have been setting fault codes:
P0131 O2 low circuit voltage Bank 1 sensor 1 (lean condition)
P0151 O2 low circuit voltage Bank 2 sensor 1 (lean condition)
P0171 Fuel system lean bank 1
P0174 Fuel system lean bank 2

Can a consistently high fuel pressure cause a lean condition??? I was thinking that I was having a low fuel pressure problem.

Thanks,
Omar