Print quality suddenly decreased significantly

Hello!

I've been printing with good quality for a while, but now something has happened. When the extruder extrudes material, it looks like the material doesn't come out at a constant speed. I think this makes the filament come out too late some times, which contributes to an awful print quality.

What do you think would be the most likely cause for this?

I would guess it has to do with the nozzle, and that the filament needs to build up pressure in the hot end in order to get out of the nozzle, then when the filament get out, the pressure drops and the cycle starts again. I've tried cleaning the nozzle, but it doesn't seem to help.

What about extruder gear? Is the idler pressing hard enough?
Are the teeth of the gear sharp and clean?
Are the grubscrews for the gear tightened?
Do you see the extruder skipping steps or grinding through the filament?
-Olaf

Quote
o_lampe
What about extruder gear? Is the idler pressing hard enough?
Are the teeth of the gear sharp and clean?
Are the grubscrews for the gear tightened?
Do you see the extruder skipping steps or grinding through the filament?
-Olaf

What about extruder gear? Is the idler pressing hard enough?
How do I know this? I've had problems with the gear slipping on the filament before, but that time it made ticking noises. This this there are no noises like that.

Are the teeth of the gear sharp and clean?
Yes

Are the grubscrews for the gear tightened?
Yes

Do you see the extruder skipping steps or grinding through the filament?
Nope!