Check the thermostat, if that's the problem you'll be looking at a 5 or 10 dollar bill if you do the work yourself.
i can't b sure 1 replace thermostate 2 same time reverse flush with good chemical,,,entire system 3 you got to realise after 13 yrs original radiator may be gone,,,water pump gone for sure,,,hoses cant last over 6/8 yrs; 4 other things,,,tuned up,,,bad running will heat it up ,,,,50/50 coolant/water...clean and full
Simple overheating is rarely the water pump. In most cases water pump failure means either a leak, which is visible as dripping from a weep hole under the car near the timing belt cover, or as a seized shaft, which would mean the engine would quit running immediately and probably be seriously damaged by failure of the timing belt that powers the water pump. Having got past that, consider the conditions of the overheating. If you are losing coolant, start with that. Verify the loss is not because of a head gasket by the simple test: with the engine cold, remove the radiator cap. Start the engine and place the palm of your hand over the radiator neck where the cap came off, and pinch closed the hose to the reservoir. If you feel steadily rising pressure within 3-5 seconds (if the idle is surging, ignore those changes) that is bad news for the head gasket. Otherwise move on. Look for leaks at the end of every hose by feeling with a clean paper towel on your hand, and look for whitish streaks around the top and bottom of the radiator. If coolant is not disappearing, the overheating must occur when in slow traffic or idling, or on the highway, or all the time. If it is when going slow or idling you probably won't see the fan running when it is hot. If it is on the highway, or if it gets hot and stays hot all the time, the radiator is probably plugged with hard water deposits from using tap water to dilute the antifreeze.
You check the water pump by looking at it! Underneath the input shaft of the water-pump is a small weep-hole that leaks coolant if the bearings and seals are shot. If there's no leak in that location absolutely nothing is wrong with the water-pump regardless what you read above. Change the thermostat with a factory OEM unit. Remove the radiator cap when the motor is cold. If the radiator return valve on the bottom is brown and dirty the entire cooling system should be drained, flushed and cleaned. The heater core and radiator cross fins are probably plugged full because of years of not changing the coolant. Is the electric fan working? When the motor starts to overheat, wrap a gloved hand around the top radiator hose. If it's barely warm the thermostat is sticking closed. If it's hot the radiator and entire cooling system needs to be cleaned with Prestone Super Radiator Cleaner.
