Toyota Repair: 98 camry v6 overheating, camry v6, head gasket

Question
my camry stays at the same temperature, horizontal needle on the guage, all the time.  recently situations cause it to rapidly spike towards the red:  excessive idling, climbing a hill with or without the a/c on.  If the a/c is on I turn it off and turn on the heater to bring the temp back down just as quickly.  I suspect the fans.  How do you check the fans before dropping a bunch into a new water pump or radiator?  The engine is high mileage but well maintained.

Answer
You can open the hood and look at the fan if turns On, use volt meter to check fan resistens or apply direct power to it and see if it works. it will take time when idles to turn on the fan. Also may have problrm if air pockets in your cooling system. is your fluid level going down. if you loosing coolant but not leak is there, open rad while eng running check for bubles. could be head gasket.