Hi everyone,
I’m facing a frustrating issue with my BambuLab P1S that started recently, and I’ve gone through extensive troubleshooting without success. Here’s a full summary:
- When printing multi-color objects using the AMS, after a color/tool change, the first few lines do not extrude any filament
- After a few moves, extrusion starts normally, and the rest of the layer looks fine.
- It happens regardless of the model or filament used.
What I’ve Tried (No Success):
- Cleaned and lubricated rods, cleaned extruder gears, AMS internals, PTFE tubes.
- Verified correct loading and filament tension.
- Tried with different filaments, including Bambu brand.
- Swapped nozzle (even tried 0.2mm).
- Downgraded firmware and Bambu Studio to the same version as working printer.
- Factory reset the printer and reinstalled software.
- Printed the same 3MF file on a friend’s P1S — prints perfectly.
Bambu support reviewed my 3MF and said:
“The issue appears to be insufficient extrusion flow and a short inner wall path. When filament isn’t extruded immediately, it’s likely due to retraction and delayed recovery. Try increasing flow and reducing speed.”
However, the exact same file works flawlessly on another printer without any changes.
Has anyone experienced this delayed extrusion after tool change on P1S?
- Any way to test extruder motor health?
- Is there a way to increase post-retraction prime volume just for tool changes?
- Could this be a hardware issue that needs warranty service?
Any suggestions or tests I could try are appreciated.
Here’s a short video showing the issue after the AMS color change:
