2002 Trail Blazer 4.2L Vortec Engine Code P0171: Diagnosis and Solutions

Model: Trail Blazer Fault Code: P0171 Posted: 2009-05-18 18:03

I'm unable to identify the root cause of this OBD2 code P0171 on my 2002 Chevrolet Trail Blazer with a 4.2L Vortec engine. After clearing the fault code, I drive the vehicle and the check engine light reactivates within one to two minutes. I've already checked for vacuum leaks, verified fuel pressure (approximately 60 PSI), confirmed that the oxygen sensors are functioning properly, inspected the MAP sensor, and cleaned the injectors. All these components appear to be in good condition. However, the P0171 code persists. Has anyone else experienced a similar issue with this model? Any insights or troubleshooting steps would be greatly appreciated.