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Q: There is a smell when the heat is on

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Sweey smell sometimes when heater on. It's not all the time and when looked under the hood the coolant overflow was normal

A: Hi there. The sweet smell is coolant leakin...

Hi there. The sweet smell is coolant leaking and the smell of the coolant is going through the cab vents. Check the heater core for any leakage, and look under the dash or on the coils of the heater core for any fresh coolant or steam. The only way you can smell the sweet coolant smell when the heater is on is either a heater core that is leaking or an engine coolant leak with the blend doors open to the outside air.

If you need further assistance diagnosing your vehicle, then seek out a professional mechanic, such as one from YourMechanic, who can come to your location to help you determine the source of the smell while the heater is on.

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