I've never had trouble with my car before. I've had it for three years and it gets regular maintenance.
I recently drove from Iowa City to St. Louis, and about 1 hour into the drive my car began to run very very hot. It normally runs about half way between " H" and " C" but this time it was dangerously close to the red line.
I stopped at a repair shop on the way, where a mechanic concluded that I was low on coolant and poured plain water directly into the radiator (although when I looked before, the overflow container was full).
After adding this water, my car ran at normal temperatures for three hours, after which I stopped at a rest stop. When I started the car up again it immediately began to run very very hot even though it had been sitting for an hour and hadn't been running hot when I first stopped.
I took the car to a Dobbs repair shop once I reached St. Louis and they were unable to make the car overheat. They told me they let the car idle for 1 and 1/2 hours and drove it on the road for 10 minutes.
Also when the car was returned to me the air conditioning did not work anymore, even though it had been working when I dropped it off at the shop.
The next day when I tried to return to Iowa City, only 45 minutes outside of St. Louis, the car began to overheat again.
I have to be driving at high speeds to get the car to overheat, but it will also overheat in stop and go traffic (after the initial high speed driving)