When my WP went it didn't give me any warning, just shot into the read REAL quick. AFAIK, they usually just die? How many miles you got on yours?
Sounds more like it could be a fan issue to me, keep in mind that if you aren't moving with a lot of air going across the radiator and the fan isn't pulling it across it won't do it's job that well and thus your engine will run hotter (not sure if you knew this or not, so I figured I would throw it in)
HTH
-Pete
