2003 e320 code
P0123
Now what does that actually mean? It may mean you have a bad throttle position sensor (and it may not). If your code reader is more than just a simple reader, it may be able to show you the behavior of the TP. The thing to look for is a steady transition (%) in the TP as you press the throttle through its range with the engine running. Not a jerky change in the %. A smooth press of your foot should result in a smooth change in %.
As for symptoms, you could get transmission or other issues with a bad TP sensor. If you have no symptoms of that, perhaps you could clear the code and see if it returns.



