Problem was very intermittant and hard to diagnose for many months - took it to shop and they couldn't duplicate the problem. Now the problem is repeatable but I'm getting widely varying diagnoses and costs. Maybe someone here can help...
96 Taurus, 3.0 liter V6, VIN U...In stop and go traffic the car starts to overheat (this was intermittent for a while but now happens regularly). On interstate the temperature is about normal but heats up rapidly when I hit the exit ramp and slow down to 25 MPH or pull into the rest area. Some said thermistat so I replaced that - no help. Some said clean and flush cooling system and add fresh coolant - did that (it was time anyway) and no help. One shop is now recommending radiator replacement at $690 (labor intensive because front bumper/grille/headlights must be removed). One shop says water pump but another says no because the pump isn't making any strange noises. All have done a pressure test and say that is fine. This model Taurus uses coolant reservior so their's no radiator cap on the radiator to be able to visually look inside the radiator.Here's some things I've noticed -
1) upper radiator hose from thermistat to radiator is hot and pressurized at normal or elevated operating temp 2) according to one mechanic the lower radiator hose from radiator to water pump seems significantly cooler than it should be (I can't reach it) at normal or elevated operating temp. This suggests restricted flow through the radiator. 3) heater hose is hot near water pump but cools rapidly as it approaches the firewall 4) if I turn on the heater after the car warms up it starts blowing warm air, but usually cools down to approximately 80 degrees within about 2-3 minutes - the faster the car is moving the faster it cools off. If I turn off heater and adjust temp back to low for a while, then turn heater back on and adjust temp to high, it starts blowing warm air and cools rapidly again. 5) this car uses 2 electric fans on radiator and both "appear" to be functioning normally.Thanks in advance for your help,
Phil