P0121 GMC -

Question

Here is my actual code: P0121 Throttle/Pedal Position Sens A CKT RNG Perform. I have already replaced Accelerator Pedal/Module Sensor.

Answer 1

P0121 Throttle Position (TP) sensor 1 performance

This is more of a MAF (mass air flow) problem if the engine is a flex fuel. Do a MAF airflow cleaning and a throttle body cleaning it usually resoved by doing this.