The Saturn Ion’s heater core is within the heater/air conditioner module, which is located below the front center floorboards. You must disconnect the nearby Body Control Module first, and you have to remove the front console to do that. Consult with an expert first.
Tools Used: Tools, Replacement heater core, Wrench, Screwdriver
Replace Heater Core
Remove the Old Core
Drain the Ion’s engine coolant from the water pump (remove the surge tank cap and drain bolt). Disconnect the heater outlet and inlet hoses by removing the clamps.