I guess it had to happen at some point. Tonight my S70 overheated on the highway. My concern is that I damaged my engine some how. Here is what happened and maybe someone can shed some light on any possible damages.<p>I'm driving in 63F at around 85MPH when I notice that the temp. gauge is just below the first red bar. I immediately pulled off at an exit and shut down the car and opened the hood for 10 minutes. The engine fan continued to run even with the key out and there was a slight chemical smell but no steam. The coolant vessel was releasing small amounts of steam. An AutoZone employee was very nice and was biclying by stopped and opened the coolant over, which resulted in coolant dribbling out along with steam. Not a giant erruption, but enough to make a mess. At the end of the 10 minutes, I put the car into POS II and the gauge read normal. At 12AM in a scary place, a close friend and the Autozone employee told me to blast the heat, keep it under 2500 RPM and watch the gauge, and I should be able to make it back to my garage. I did and she is sitting in her parking spot. The way home the gauge read like it normally does. I left the hood open for about 15 minutes and heard air hissing from the coolant vessel. <p>For some history- 5 months ago when I was in the middle of a New England winter, my Temp would always be on the cold side, and during really cold weather, the car would never really warm up unless she was idle. Does it sound like the engine thermometer failed tonight? Since the engine never stalled, died, steamed, or put the needle in the red, do you think that I am safe from engine damage?<p>The next time I start her, we'll be going to the dealer...