Ugh! I have a weird problem. Basically, the extruder stepper motor ejects filament for two seconds, pauses for about two seconds, ejects for two seconds, pauses for two seconds and so on. This is on a Makerbot Replicator 2x. Only have one nozzle setup, with ABS. This is happening while I am trying to "load" filament, or trying to print. Presently I am trying to load filament, heating plate is at the bottom of printer, so there is no chance of the build plate being too close to the nozzle. What I have done so far; changed out all top end parts from the stepper motor to nozzle (stepper motor, extruder, throat, hot end, heater, thermistor, extruder gear, idle bearing, and fan). Changed out all wiring and double check continuity. Changed out stepper drivers. Bought new filament. Made sure extruder fan is blowing the correct direction. Made sure the throat/nozzle connection is tight. Have tried steel throats and silicon throats. I have seen no indication of filament ooze or clogs/jams. Tried printing from 210 to 250. Regardless of what I do, the same result continues, the filament is go/stop, go/stop, go/stop. Again, the extruder is just printing into mid-air because the plate is at the bottom of the printer. Any ideas or help would be most appreciated!
Have you tried going to Help > Configuration Assistant, and re-downloading the Replicator 2X profile? We use those exact settings with our machine here, so that would at least rule out any software configuration issues. At that point, more likely causes could be firmware or electrical problems.