Have your cooling system flushed, coolant changed, and thermostat replaced before you go. Check the grille and the front of the radiator for obsructions (dead bugs, dirt, leaves, etc.) Spray the outside of the radiator down at the car wash to remove anything you find.
If it starts to get warm on the drive, slow down. Lower RPMs = less heat. If it gets too hot, find a place where you can pull safely off the road and let it cool before moving on. Turning the heat on was a good idea, but I wouldn't want to overheat the baby in order to save the car.
Replace the thermostat? It could be sticking in the closed position and not allowing coolant to circulate back through the radiator.
A 1991 Subaru Impreza might overheat because of a leaking cooling system or because of a damaged thermostat. You might also have a damaged or leaking radiator or a cooling fan that is not working.
One reasons a Subaru Forester may overheat is because the radiator may need replaced. Another reason could be the thermostat.
start with checking thermostat
Check coolant level, and radiator fan operation.
It's the current flowing in a wire that causes it to overheat.
There are many ways that it can overheat. Coolant loss, blown head gasket, stuck thermostat, clogged radiator ar only a few. You would have to consult a mechanic to know for sure why it is overheating.
Where is the knock sensor located on a 1999 Subaru Forester?
I have found the common causes for this are, a plugged heater core, and a poorly working water pump. The radiator could also be plugged.
You may need to replace the radiator thermostat and gasket.
You could have a bad thermostat, just because its new doesn't mean its good, TRUST ME ON THAT, or you could possible have an air pocket in the cooling system.
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