Can't identify print issue...

[Birdman1]

Hi guys

Have been printing for months now with minor issues but now i am stuck

If one checks the pictures below then one can see the infill in the right top corner is acting strange allthough the full remaining part is perfect. The thing is that this reaches out until the top , so finally also the top layer gets printed weird in that corner.

Now this is my blog http://birdmangoesmalyanm180.blogspot.be/ and normally my prints are really good.

What could cause this to happen and why only there?
It really puzzels me.

Tried already the following things
Change infill percentage to higher - seems to be wurse now
Change the extruder export added 5% no significant change
Changed the nozzle size from 0,4 to 0,36. Just for experimenting didnnot solve this.

Is this a software issue or a hardware issue
Who is willing to help me out?
Many thx

Birdman

[Heutinck]

try slowing down your infill speed, it may not have enough time to solidify properly. whats the fan speed as well.

[dkightley]

At a guess from the little info you have provided and the dark photos it may be either one or a combination of under extrusion and too few top layers.

Can you attach a factory file for this part ( File menu==> Save Factory file as...) and a clearer photo of the whole part please.

[billyd]

Looks like retraction issues. Do you have any coasting set? Negative restart? Or it could be firmware related, again with pressure control of your extruder.