Just a quick query as to who the OEM supplier was for glow plugs on the HDi series of engines. Specifically the 8v 1.4 HDi of 2001/2.
The ones I removed were NGK, and knowing their reputation in the XUD series I'd be looking to avoid them unless they were original equipment. (obviously if they were the OEM supplier that's good since they've likely lasted 16 years/100k miles, but to my mind they looked newer than that hence my question).
So the 206 has had at least one set of replacements & they lasted at least 2 1/2 years since they've been in as long as we've had the car. (and judging by how clean and shiny they looked, not a great deal longer than that either).