Ok I have a 2000 Nissan Pathfinder with 110, 00 miles. The antifreeze hadn't been changed for about 3 years when I noticed that the engine was running very hot (guage all the way into the red). After determining that the thermostat was opening, I added some antifreeze, because it appeared to be a little low. While driving later that day, the temperature seemed to drop, and then rise. It continued like this the whole time.
The next day I took it to a shop to have the cooling system flushed hoping to remedy the problem. The mechanics however told me I had 3 leaks:
1) at the waterpump
2) upper water outlet
3) throttle body thermo-element seal
^^this one I've found the others I haven't been able to see.
They gave me an estimate of $600 labor + parts for the 3 leaks, the timing belt, and coolant flush.
Now is this a good price, should I shop around a bit, or are some of these fairly easy to fix by yourself?