Bank 1 and 2 lean codes

[kendrick newborn]

Hey everyone, I have 2004 chevy tahoe 5.3 and it keeps throwing bank 1 and bank 2 lean codes. The only thing that I've noticed is it has a inconsistent engine shake at idle, I did look for vacuum leaks but I haven't found any yet. Has anyone delt with this issue before? The only thing not stock is the previous owner installed a cold air intake

 

[strutaeng]

Lean on BOTH banks is usually a fuel delivery issue, especially when both banks fuel trims are identical and stay the same (of worse) under engine load.

 

[nonickatall]

So check first the fuel pressure. There is a connection on the rail for that purpose.