How to fix Chevrolet or GMC P0174 engine code: System Too Lean (Cylinder Bank 2)
A P0174 Code is set when the Bank2 upstream sensor1 oxygen sensor reports a lean airfuel mixture.
A lean condition exists if the engine is getting more air than fuel in the cylinders. (Air/Fuel Ratio is wrong)
P0174 Code can be problematic since it can be caused by many things.

How To Test Upstream Oxygen Sensor 1 Video:    • How To Test Upstream Oxygen Sensor 1 ...  

How To Test MAF Sensor Video
   • 2 Ways Test a MAF Sensor with a LowC...  

Possible Causes of a Chevy/GM P0174 Code
Oxygen Sensor (Bank 2 Sensor 1)
Exhaust Leak
Mass Air Flow Sensor (Codes P0100P0104)
Clogged Fuel Filter
Fuel Pressure Regulator
Weak Fuel Pump
Vacuum Leak
Bad Fuel Injector

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