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X1 and P1: the extruder clicks, chews the filament or is clogged (cleaning and greasing)

Guide based on the manufacturer's official documentation; usi3d has not yet verified it on a machine.

Technology: FDM · Brand: Bambu Lab · Symptoms: The extruder clicks or skips, The extruder grinds or snaps the filament, Clogged nozzle or hotend · Updated on 9 October 2026

Symptom

The X1 or P1 extruder clicks or grinds, there is dust or filament debris on the yellow gear, the filament comes out chewed or deformed next to the gear, or filament will not go in or out of the extruder.

Likely causes, from most to least likely

  1. Dust and filament debris building up inside the extruder and on its gears over time.
  2. Too much heat inside the toolhead, deforming the filament next to the drive gear.
  3. Broken or stuck filament inside the extruder.
  4. Worn or ungreased gears.
  5. A stuck extruder filament sensor giving false readings.

Checks to tell which one it is

  • Remove the front cover and look at the yellow gear: if it is dusty, it is time to clean.
  • With the hotend removed, extrude and retract: if the filament does not move forward or back properly, the extruder is blocked.
  • Pull the filament out and check it for bite marks or deformation.

Before you start

Before taking anything apart, cleaning or adjusting it, switch the printer off and unplug it, unless a step says otherwise, and do not touch the nozzle, the heater block or the bed until they have cooled down. If in any doubt about electricity, heat or moving parts, stop and ask a professional.

Step-by-step fix

  1. Quick clean with air

    Switch the printer off. Blow compressed air over the yellow gear; if you remove the hotend, also blow up underneath the extruder to clear the dust inside.

    Check: No visible debris remains and the clicking stops.

    If that does not fix it: Remove and clean the extruder (next step).

  2. Remove the extruder

    With the printer off and unplugged, remove the front cover and disconnect the cables (filament sensor, fans and hotend heater), taking care with the sensor's flat cable. Keep the cutter lever pressed and loosen its screw; remove the three extruder screws, remove (on the P1, loosen) the two filament guide screws, push the guide to free the PTFE tube and lift the extruder out.

    Check: The extruder is out without forcing any cable.

    If that does not fix it: If a connector is glued, soften the glue with a hair dryer (never a heat gun) or cut it with tweezers; if the PTFE tube will not come out because of the clog, Bambu Lab says you can cut a short piece off next to the coupler.

  3. Clean and grease the gears

    Remove the two hotend screws and separate the hotend. Remove the extruder back cover, loosen the tension screw and take out the large gear without losing its bearing. Push the debris out of the inside with a piece of filament, brush the gears clean and apply a very small amount of grease to the idler gear teeth and the sides of the drive gear, wiping off any excess.

    Check: The gears are clean and turn smoothly, with no grease in the filament path.

    If that does not fix it: If a gear is worn, replace the extruder gear kit.

  4. Reassemble and test

    Refit the gears and cover, tighten the tension screw until it clicks into place and turn the large gear by hand. Refit the hotend, the extruder, the cutter lever (tighten gently), the PTFE tube with its support as high as possible, and reconnect the cables properly aligned.

    Check: After power-on, manual extrusion runs smoothly and steadily.

    If that does not fix it: If the printer reports an error, check that every connector is the right way round and fully seated.

  5. If the filament sensor is at fault

    If the green extruder dot stays on with no filament, remove the detection switch following the guide for your model, take out any filament fragment and check that its magnet springs back by itself.

    Check: With no filament, the dot turns white.

    If that does not fix it: Contact Bambu Lab support.

Prevention

  • On the X1, Bambu Lab recommends checking and cleaning the extruder gear weekly; on the P1, as soon as you see dust on the yellow gear. Replace the gears if they look worn.
  • With PLA and PETG, keep the toolhead from getting too hot: open the door or the top cover.
  • Grease sparingly: grease must not reach the filament path.

Still not fixed?

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Printers it applies to

Bambu Lab X1 Carbon, X1, X1E, P1S and P1P.

Official sources

This guide summarises the official documentation linked here:

This guide is general information: usi3d has summarised it from the official documentation linked here, and it may not match your model, its version or its firmware. If in doubt, follow the manual and the support of your printer's manufacturer. You decide what you do with your machine, and working on it may affect its warranty.

Products that may help

Chosen for the symptoms in this guide and the printers it applies to, not for the commission. Check that they work with your printer before buying.

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