I have only read of the tip breaking off in some, which is likely worse since it would rattle around in the pre-chamber. At least the innards blowing out gave the broken part an exit path. I can't make out the brand of the failed one (new ones appears to be Bosch). Perhaps add to the running thread about glow-plug experiences. So far I have found the CFP (Chinese) brand to be one to avoid and VSP (Taiwain) appears OK. It looks like the internal pressure seal in yours is made by an O-ring. I wonder if all are constructed like that.

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1984 & 1985 CA 300D's
1964 & 65 Mopar's - Valiant, Dart, Newport
1996 & 2002 Chrysler minivans