Hi Russ, it sounds like the temperature switch is bad. It is located under the hood, front engine area, driver side, end of intake manifold, mounted in the block. U should be able to test it w/ an ohmeter as follows: disconnect wiring (check for loose, corroded, etc as that could be the problem) remove temp. switch, place in an old pot w/ water on stove, w/ temp below 99 degrees, connect ohmeter to terminals, reading should be zero. Heat water to above 99 degrees, check , should read infinity. If it fails this test, it's time to replace it. Good luck, let me know how u make out Curt from Connecticut.