Extruder clicking, and than clogging right at first layer.  

Extruder clicking, and than clogging right at first layer.

Three months ago I had issues with clicking sound on my i3 mk3s extruder, followed by extruder clogged right on the first layer. The clicks happened even while loading filament for the first time. After that I decided to open the extruder and check and clean each part. I cleaned the heatbreak and heatsink and added the thermal paste bought on prusa website. The clicking sound didnt stop, and I wondered that maybe the problem was on the filament. So I bought some prusament PLA to see if the problem was with the local PLA brand. The clicking sound followed by the clogged nozzle persisted, and this time I thought maybe the problem was with the nozzle. So I change the nozzle for a brand new 0.4mm default nozzle. Still the problem persists.

After that, i tried a 1 mm nozzle and, SURPRISE! The extruder is working perfectly without any clog. Altought that is very exciting to print with such a "huge" nozzle, I have to go back to the 0.4 nozzle for achieving more resolution. After the experience with the 1mm nozzle and renovated hope, I replaced the extruder with a 0.4mm nozzle and ,unfortunatelly, it still doesn't work.

Any ideas on how to solve this issue? SOS i need help.