I have replaced all 4 O2 sensors as well as cleaned the mass air flow sensor, egr and checked for vacuum leaks. All is good yet I still have codes reading banks 1&2 showing too lean, also #1 cylinder misfiring. But when engine warms up all seemed to run without misfire?
Anybody have any ideas what else problem could be?

 

there may still be a vacuum leak.
i have to ask, does your 4x4 work properly?

 

??? Last time I had in 4-wheel drive was probably a year-and-a-half ago so I don't really know I'll put it in gear and check it out tomorrow what should I be looking for?

 

the 4x4 is vacuum operated, so if there is a vacuum leak, the 4x4 will not be working, or be very slow to work.
the actuator on the front axle is controlled by the 2 solenoids on the firewall by the battery.
There is also a vacuum reservoir in the right front fender. I have pics in my gallery to help out.

 

Awesome info, thank you so much. I will check that out.