Can anyone help? Thanks.

2002 K1500 Chevy Suburban, 5.3 Liter Flex Fuel, 193,500 miles, just replaced
plugs and wires.

Cold start, runs rough, tripped codes P0171 (2 - one for bank 1, one for sensor
Bank A) and P0174 (also 2 - one or bank 2, one for sensor bank B). Runs great
once fully warmed up.

Intake manifold pressure bounces round 11- 12 and goes to 10 steady once warmed
up

 

You may want to check the air filter. The MAF sensor may be dirty, as a result of the air filter being clogged. Are you running a K&N filter that uses oil. It is possible that you have put too much oil on the filter. Is this is the case, get a K&N cleaner kit and clean the filter and re-oil conservatively. You should also try and clean the MAF sensor or look at replacing it.

You are doing well with 193,000 miles on truck.