Why did my angle grinder die?
The Intermittent "sputtering" is sign of a loss of power going into the motor windings. there is pretty much only two ways this happens, A: there is a short somewhere (plug, cable or switch) or B: the contact brushes are dead.



If mild shaking of the grinder added to the sputtering, I would say its the brushes. This is an easy fix, since you just need to get access to the brushes and change them. However, for many cases (with cheaper makes) its about the same cost to replace the unit.