Question

2007 Chevrolet Avalanche LTZ 5.3 with engine code P0121. Code reads TPS/Pedal Position Sensor A CKT Range/Performance

Answer 1

P0121 Throttle body airflow performance

You set this code when the predicated airflow is outside the predicted MAP range. This code is known to set without setting the CK ENG LT. do a MAF (mass air flow) cleaning and change the air filter if necessary.

Answer 2

P0121 CHEVROLET Code - Throttle Position Sensor 1 Performance

Read more: https://www.autocodes.com/p0121_chevrolet.html