I think what you may have is an exhaust leak which is being drawn into the car via the heating system intake. so you need to locate what is leaking, fix it, and then it will not be sucked up into the heating system. if the fumes are sweet smelling however, you have a leaking heater core or a bad hose/clamp.
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I think what you may have is an exhaust leak which is being drawn into the car via the heating system intake. so you need to locate what is leaking, fix it, and then it will not be sucked up into the heating system. if the fumes are sweet smelling however, you have a leaking heater core or a bad hose/clamp.