Questions and Answers

Ford Aerostar Not Getting Good Heat Q. Hi, I have an 1989 Ford Aerostar, V-6, 3.0 liter 118,000 miles on her. The heat has always been warm at best, and never has really blown HOT air. I have changed the thermostat about three times now in the 14 years I've had it, and the coolant seems to be fine, within a good range.

The engine temperature gauge shows right in the middle, normal, when the engine is fully warmed up, etc, and you can even see the thermostat working on that gauge. Do heater cores fade? Or do they either work or don't work?

Thanks,
Bob

A. Heater cores do not fade but they do get plugged up sometimes. If someone used stop leak on it, stop leak will plug up a heater core real fast.

Here is a way to see if the heater core is plugged up. Disconnect both hoses from the heater core and take a garden hose and slowly send some water in one of the tubes sticking out of the heater core. Then watch to see if you get water out of the other one. If so increase the water pressure and see if the discharge is increased out of the other. If the water flow increases than the heater core is probably okay.

Most heat problems that are not from bad heater cores but usually from a bad heater control valve. I am not sure witch one you would have but the heater hose would be connected to it.

Also do you have air in this car? If so the heater control valve is part of this system and it is not that hard to change.