P0121 Pontiac G8
P0121 is a somewhat common trouble code with the Pontiac G8. It’s an OBDII code and has to do with the Throttle Pedal Position Sensor. It is relatively serious problem since it leaves your vehicle in failsafe mode. P0121: Throttle Pedal Position Sensor → Switch (TPS) A Circuit Range → Performance Problem OBDII code P0121 … Read more