Ender 3 V3 KE Bowden tube jams

Ender-3 V3 Printers Creality Ender-3 V3 (Regular)
1

I’m at my witts end here. I’ve done calibration tests out the wazoo, reset everything back to zero state, changed to a unicorn nozzle, replaced the extruder, checked every single screw, checked the gantry to be level, played with the z offset, and I’m just about done with this. I’ve even tried the thin bowden tube that comes with the ceramic upgraded hot end and purchased and cut a normal bowden tube also.

But for some reason I am constantly getting jams between the extruder and the hot end. I’ve played with temperatures from 200 to 230 and ran temp tests. But just can’t get prints to complete…

Here’s the picture of the latest jam in any help or ideas would be desperately accepted

IMG20250625173014
IMG202506251730141920×2560 176 KB

2

Hi
This sounds like a failing hot end fan causing heat creep up the extruder and past the heatbreak.
These small fans are known to fail.

3

Yup, replaced it about two weeks ago along with changing the entire hot end assembly to the unicorn style ceramic upgrade after the hot end heat break blew out.

What’s weird is that on the base layer when calibration comes out the bed is perfectly level less than 0.10 difference across the calibration points… However the left side seems under extruded and the right seems over extruded when printing a first layer. I checked the gantry with the “soda can test” and they are both dead on level