I recently bought a '00 civic coupe, and just today while sitting in traffic for around 30 minutes the antifreeze started to boil in the reservoir (only about 60 outside). So I pulled over turned the car off an noticed that it boiled for about 5 more minutes until it stopped. I thought maybe the person I bought it from may have put water in the antifreeze an diluted it lowering the boiling point or maybe the fan wasn't cycling on (I don't remember if it turned on I was to annoyed at traffic). <br> Anyways the car temp gauge was not even at half way and I normally drive 30 miles a day on the highway and never have a problem and no it's not blowing white smoke. Both the hoses were hot so I know the thermostat works and the hoses are fine. So I'm wondering what do you guys think it is? I'm going to check the fan tomorrow and the relay an fuse to make sure that is cycling on and hopefully the world doesn't end on Saturday so I will be able to look at it more thoroughly. Any input is greatly appreciated.