XK8LS1

Any advice would be much appreciated. Build complete except for following:
Problem
1. PO172 & PO175. Runs rich both banks
2. Fault codes prevent catalytic converter & O2 monitor from coming on
3. Fuel trims are -15
Symptoms
Starts easy. Idles smooth til warms up. No codes at idle. Codes appear during GM drive cycle on acceleration to 45 mph+ or on deceleration to 20 mph. Fuel system goes closed loop and all other systems are ok. Rough idle, stalls, hesitation after warm.
Tests I have done:
MAF (new) is .79 to 1.2 lb/m @idle.
MAP (new) manual vacuum is 18 in Hg & steady at idle.
Fuel pressure regulator = 52 psi key on engine off; 50 psi @ idle.
Engine 150 psi on all cylinders: oil pressure 44psi @ idle.
New plugs, wires, thermostat, TPS, Injectors s( supposed to be tuned to 42lb
All vacuum leaks fixed after home made smoke machine test.
HELP?

2xLS1

iTrader: (25)

Your fuel trims are too negative. What I bolded is more than likely the problem. You need a way to read the tune file out of the PCM to see what has been done. No other way around it when things like injectors have been changed. Lots of bad tuners out there. A few more details on what you have including PCM used, but anyone would still need to see the calibration in the PCM to really help.

XK8LS1

Thank you. I will find someone that can check/adjust the tune.