Does my extruder need replacing

Bambu Lab A Series Troubleshooting
1

I have a Bambu A1 printer. I print a mix of PLA and PETG. My printer has about 2400 hours on it with no issues. I have started getting extruder not extruding properly alerts. I opened up extruder and cleaned the gear wheel and blew out a very small amount of dust. Still getting the alerts. I can set up a job, the printer will go through all the preps such as purging and loading filament, dynamic flow calibration etc. with no issues. Then, when it starts the print job it will give the alert. Watching the printer, it appears the extruder is not pushing the filament. The extruder wheel turns a little, then starts clicking and it will jump forward and then back repeatedly while making a clicking sound.
Is this the indication of a dying extruder, worn extruder gear, or what. I have tried four different 0.4 nozzles with same result. I use almost exclusively Sunlu PLA and PETG filaments and have never had an issue. I did get it to run last night on a 0.6mm nozzle.

If this is indication of dying extruder do i replace the entire extruder unit or can you somehow just replace the little gear wheel.

Any thoughts from you guys?

2

This should probably have been posted in the A series subforum rather than makerword section for more replies.

It can be a lot of things, from blockage (probably not as you have swapped nozzles), stuck somewhere else in the system /tubing or AMS).

You say you got it running with a 0.6 nozzle, is the machine set up with the correct hardware setting when you run the others? Is it trying to feed a 0.6 nozzle amount of plastic into a 0.4 nozzle ?