Engine Overheated!

The other day my engine started to smoke and it was coming from the coolant reservoir. The coolant inside was also boiling. I read in a manual how to check the thermostat. It said that if the top hose to the radiator is cool that the thermostat is closed shut. somebody also told me that the coolant in the radiator should go down when I push the gas pedal but it goes up. It gets hot even quicker when the A/C is on. I've never flushed the radiator and I think that sediments might have gathered at the bottom. Can somebody give me some insight on what could be the problem?

[ShEaNy]

is ur fan working properly? my freind is having the exact problems with his car..:o

The fans don't turn on after the car has been on for a while. But they both turn on when I turn on the A/C. Then when I turn off the car after it starts to heat up, only one fan is on. Is that right?

[ebpda9]

yup that sounds right. and i think it is your radiator that is playing dumb on you. i had the same problem but it did it only once and after 3 months the radiator blew out. never had any problems since. also get som red line water wetter and add it to your coolant. i noticed a drop in running temperature without changing the thermostat

Thanks. I'll check it out. My car has been sitting there for a week already.