Issues with layer "tearing" - Beginner

Hello, i have an issue with my Reprap Mendel Prusa I2.
When i print, i tend to get some tearing in some layers.
Picture:

What can cause this? Warping?
(sorry for the dark image, the thing i am trying to explain is the earing between the legs of the marvin figure)

Just did another test print. Same result, tried lowering bed temperatures and extruder temperature (i'm printing with PLA).

Can nobody explain this to me?

I found it quite a surprisingly hard print.
I did it in abs with a 0.3mm nozxle.
And i couldnt print the ovefhangs underneath till i put quite a lot of cooling on the nozzle as it printed.
You need to up the temp a little with the fan.
But once i added the fans it came out perfect.

Gordon

So i need to boost the cooling?

Or should i raise my extrusion temperature & Bed temperature?

I used abs that i dont usually need to cool but needed to cool for this print.
So i went from no fan to about 30-40% fan on mine.

Pla needs the fan more than abs for any print.
So with your pla try increasing your fan speed some more and your nozzle temp a few degrees.
Is your fan ducted to the nozzle? Or like mine a fair distance from the nozzle?
If its ducted to quite close to the nozzle you probably dont want it on full blast.
But increase it bit by bit.

Gordon

Thank you for your replies!

How ever, i have been getting way better results, since i lowered my nozzle temperature.

My fan is ducted close to the Nozzle. However, it's a radial fan and i'm not impressed with the amount of air its providing :/