I'm getting a free replacement sent from Etecno. Apparently they've had 5 reports this winter:
Etecno wrote:
Claims about this glow plugs are not popular, but we had five claims this winter, all from USA, I guess the very could temperature in the area have stressed the glow plugs very much, so I guess minor manufacturing fragility can show up on a few samples. We need to investigate this further and I'm in charge of collecting data for proper investigation.
edit: going through an exchange process with IDparts. Etecno is out of stock and I'm impatient.