Any idea of what the range on the stock gauge is when the temp goes over 220? I had a heater hose develope a pinhole last week and I didn't realize anything was wrong until the A/C cut out (failsafe?). I then noticed the guage was just shy of the top of the "normal" range, about a 1/8"-1/4" below the top. I turned on the heater and drove for another 5 minutes while trying to see if it would cool down. When I stopped, steam started billowing out from the broken hose. I let it cool for a few hours before replacing the hose and topping off with distilled water which I'd been warming in the engine bay.
Any chance I damaged anything? What should I check? The car seems to run strong still and I don't see steam in the exhaust.