Hey guys !

Thing happened on my main 3D printer (which have run pretty well for months) :

- Prusa I3 type
- Arduino/Ramps 1.4 controler under Marlin
- Allegro A4988 drivers
- Standalone configuration with 12864 display controler

Since 3 days ago, when I run a print, ther primary layers goes pretty good.
After a while (randomly, between the first 20 to 60 layers, whatever the part size),
the extruder motor starts to stop running momentary which creates under extrusion
and randomly no extrusion at all.

I checked and changed :
- the motor's wiring
- the stepper motor
- the Allegro driver

Obviously my printer is properly set. The boards are ventilated buy a powerfull 20x60x60mm fan, and stays cold.
I don't have any lack of power because it appears only on the extruder side. Through, I could not measure any drop on the main power.
The Arduino is a computer. It should work or not work but not randomly and after a while.
If it was the arduino, I should have experienced problems on boths axis or since the start of the print.
I wonder if the Ramps can generate this kind of problems ?

What do you think ? What should I try next ? Any Idea is welcome !

Z