P0171 Code Bank 1 lean “HELP”

[jfkelley]

LM7 / 4L60e / NP241C / LSXceleration Stage 2.1 Cam 218/227 .523/.523 HR112+3, Delphi GM LS7 Lifters & Lifter Guides , LS6/LS3 Valve Spring, Brand new O2 sensors, just drive it home from
Tuners..
I keep getting bank 1 too lean and then it runs like crap no
Throttle response have to disconnect negative battery post to reset computer ..I have checked for vacuum leak @ intake , Booster hose , exhaust manifold , PVC hoses , checked all injector connections I’m running out of ideas ..Your input would be very helpful ..Thanks in Advance

 

[MarineOne]

Need more info
What intake/ throttle body
What turning software
What computer
What exhaust
Header or manifold
Where is o2 sensor in exhaust
How close is o2 to any weld or joint in exhaust
What is orientation of 02 sensor
Brand of o2
What condition makes this happen?
Does it happen in closed or open loop
What brand injectors
What ignition system including plugs wires and coils
What coil driver

That info will help narrow it down

 

[jfkelley]

Need more info
What intake - CAI / throttle body - stock
What turning software- waiting on reply
What computer- stock
What exhaust- 2.5 Magnaflow
Header or manifold- Stock with BBK Cat delete headers
Where is o2 sensor in exhaust - upstream
How close is o2 to any weld or joint in exhaust- right below where stock manifold meets BBK header
What is orientation of 02 sensor - pointed straight to the back of the truck
Brand of o2- OE GM
What condition makes this happen? Driving down the road or after sitting and ideling
Does it happen in closed or open loop- forgive my ignorance idk what this means ?
What brand injectors Stock EV6
What ignition system including plugs wires and coils OEM GM plugs / MSDS wires
What coil driver Stock

 

[jfkelley]

Just re-checked the situation. While there is plenty of fuel, I think that the spark is either intermitt or missing on the driver's bank. The drivers side exhaust is cold and the passengers side is too hot to touch

After researching of a few forums
1. Broken valve spring
2. Bad ground on back of head (might try ohm it to make sure that wires not broken internally)
3. Bad ECU