Actually, the heater core is on the passenger side. Coolant normally leaks into the drain pan for the water that condenses when the air conditioning system removes the humidity from the air, but it depends on how the system was designed. I suspect pressure in the cooling system is causing that hot coolant to spray over to the driver's side.
Heater cores are not outrageously expensive but the labor to replace them is. On most Ford products the steering column must be lowered and the dash must be pulled back to remove the heater box and actuators. The air conditioning hoses must be disconnected so that means recovering the refrigerant, then evacuating the system and recharging it. Thanks to your politicians and the EPA, air conditioning work is also expensive.
As a temporary measure you could disconnect the two heater hoses at the firewall, then buy a plastic fitting to connect them together. That will bypass the leak and it should stop the overheating. Keep in mind though that obviously you won't get hot air from the heater, but you won't get it from the defroster either. The air conditioner will still run in defrost most, like normal, to remove the humidity from the air so it won't condense on the cold windshield and cause fogging, but since the air will be cold, it will take longer to defog the windshield. If the other guy runs a red light and causes a crash, his lawyer and insurance investigator will look for things like that to try to shift some of the blame to you. That rarely happens, but I wouldn't be doing my job if I didn't at least mention it.
Monday, September 9th, 2013 AT 2:10 AM