Toyota Repair: 1994 toyota pickup overheating, blown head gasket, coolant fluid

Question
my 94 pickup, (204,400 miles; manual transmission) was overheating when i got back in town and hadn't driven it for a few days.
i had the thermostat/gasket replaced, and it was okay for a few days; but its been going through coolant fluid rapidly and overheated again today.
its also been idling irregularly, sometimes remaining in high idle when i take it out of gear, sometimes going back and forth between a low and high idle at a rapid rate.  
i live in the deep south, so its pretty hot.....any suggestions?  

Answer
Possibly a headgasket problem, if it's a V-6 there is still a special service campaign in effect contact the toyota dealer and have them run the VIN# in the computer to see if it applies to your truck, if so you will get the headgaskets replaced at no charge.
If it's a four cylinder engine it may still be a headgasket problem or the radiator may be partially clogged up or there is a leak in the cooling system, have the cooling system pressure tested and checked for a possible blown head gasket.