Here's what you should do:
* Don't ignore it: A coolant leak is serious. Driving with a leaking heater core can lead to overheating, engine damage, and even a complete engine failure. Also, the loss of coolant can lead to significant corrosion problems in the cooling system.
* Check your coolant level: Open the hood and locate the coolant reservoir (usually a translucent plastic tank). Check the coolant level. If it's low, this strongly supports a leak.
* Inspect for leaks: Look carefully around the engine compartment for any signs of coolant leaks (greenish or reddish stains, damp spots, or puddles). Pay close attention to the area around the heater core (this is difficult to see directly but look for stains further down) and hoses. It's best to do this with the engine cool.
* Sweet smell: Does the steam have a sweet smell? This confirms that it's coolant leaking.
* Professional Diagnosis: Due to the difficulty of accessing the heater core, a professional mechanic is likely necessary for diagnosis and repair. A proper diagnostic will locate the precise source of the leak. They may need to perform a pressure test on the cooling system to pinpoint the leak.
* Possible Repairs: Repair options range from replacing the heater core (the most likely culprit), fixing a hose leak, or addressing a more serious crack in the engine block or cylinder head (less likely, but possible). Replacing the heater core is a significant job often requiring dashboard disassembly.
In short: Get your 2001 Ford Windstar to a mechanic as soon as possible to avoid further damage. Driving with a leaking heater core is not recommended.
