[mikesz]

I have a 99 Boxster, just turned 80k, have owned it little over a year. Problem I am having is when it starts getting hot here in the northeast, like 80 and up, the car runs hot and the warning light starts flashing. Last year I replaced both fans and I checked to make sure they are still working. while I was at it I cleaned the radiators. so the only thing I can think of is 1) air in the system and needs to be BURPED 2) thermostat 3) water pump. Any thing else that it could be? is there any way to test to determine if its the thermostat OR water pump? there is nothing leaking under the car and I have an S center radiator and coolant pipes I plan on installing.

anyone have any advice or thoughts?