I don't know how else to describe what happened. It was about
108F. on Sunday. I drove about thirty miles on the freeway. When
I stopped and turned of the ignition, coolant exploded from the
white tank, blowing out the black screw-in sensor on the top.

The expansion tank was dry so I suspect that something that
should be working is not working properly (like the cap on the
white plastic tank).

The threads on the tank seem to be buggered or maybe the sensor
threads are stripped in either case they don't fit without a lot
of teflon tape.

Suggestions? What all should I plan on replacing?

Thanks,

John-Reed Maffeo