This could be a problem with your vehicle's thermostat starting to stick. Your vehicle's engine cooling system utilizes a thermostat to regulate the flow of coolant around the engines water jacket. As the coolant goes around through the engine's water jacket it absorbs the heat the engine produces. It will absorb the heat until the thermostat opens and the coolant is allowed to circulate where it goes to radiator and is air cooled. It is then pumped back around the water jacket until the thermostat closes again. This process repeats itself over and over. If the thermostat starts to stick, which happens from normal wear and tear, it wont open and close properly, and the coolant can not circulate like it should, causing your vehicle's engine to overheat. Your vehicle's heater core is a part of the engine cooling system and acts like a small radiator, pulling heat from the coolant. This is why when your heater control is on, your vehicle's temperature stays normal. I have included a link below for you to go to:
I have also included for you in the diagrams down below step by step instructions for your vehicle on how to remove and install the thermostat. Please go through these guides and get back to us with what you are able to find out.
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Friday, April 26th, 2019 AT 11:29 AM