P0174 and P0171 codes
 

I keep getting these codes on my LS swap. Its an LQ9 stock other than headers and a cold air intake that I fabbed myself. I'm using the PSI conversions computer and harness. I put a fuel pump in the stock tank, and it's getting 45 psi at the fuel rail. But- it was a cheap pump off of Amazon and I have suspicions that it is the culprit of my codes. The engine has 3/8 supply and return lines.

Do I replace the pump or look to having it tuned?

Re: P0174 and P0171 codes
 

Those are lean codes and if your only at 45psi your running lean. I believe gm wants 55-60psi at a minimum. Corvette regulator most guys use is preset for 58psi. Where's the regulator on your setup?

Re: P0174 and P0171 codes
 

Well, that is probably my issue. The pump is only putting out 45 psi. I'm using the stock regulator that is attached to the intake, the engine is out of a 04 escalade. Guess I'll replace the pump this weekend and see if it helps.