A blown head gasket will not "blow" a coolant line. I do know if the engine runs overheated you have a chance of blowing a HG or warping the head. Not sure on the auto cutoff though. It would be nice if all vehicles had this option. I've seen small engines (Honda 5.5hp) that if low on oil, will kill the ignition.

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2001 E53 4.4 Alpine White, Sports Package
2000 E36/7 2.8 5 speed Bright Red w/ a HT!