I have an 06 MCS with TPR-2 Head, RMW Race headers, RMW CAM, RMW Tune, and 450cc injectors, CAI, and Straight Pipe exhaust among other things. I have an SES light on showing that I am running lean. My question is could I be running lean due to a faulty fuel pump? It doesn't make sense that I would be lean with 450 injectors. Any suggestions would help

 

ask RMW about your tune would be my first step. do a datalog and have him check the numbers.

 

What code?
Lean codes are often more inductive of a exaust leak, manifold leak or other issue....
Extra o2 gets into the exaust, and the o2 sensors sees this as unburnt oxygen...so car must be lean.....according to the computers logic.