[Under-extrusion or a bigger problem?]

Prusa Mendel I3, nozzle size 0.4 mm, material diameter size 1.75mm. Everything seems to match with the Monoprice specs. Could a clog be the issue?

[Under-extrusion or a bigger problem?]

It's not a Ultimaker, it's a Monoprice Maker Select v2, but it uses Cura. So this is definitely a physical flaw, not an effect of the settings? What is the function of the TFN/TFT?

[Under-extrusion or a bigger problem?]

I've been playing with the settings, mostly slowly down the print speed in Cura. I'm not sure why the quality of the print is so low. This printer use to produce high quality prints at much faster speeds. Is this just a setting error? Is it possible that I need a new nozzle or something else? Any advice will help.

 

Current Settings: 

Plastic type: PLA

Extruder Temp: 210 C

Fill Density: 15 %

Infill Speed: 65mm/s

Outer Shell Speed: 30 mm/s

Inner Shell Speed: 60 mm/s

Layer Height: 0.1 mm