- Coolant leak: A coolant leak can cause sweet-smelling vapor to enter your vehicle's cabin, which can condense on the windshield and cause fogging. Check the coolant level in your vehicle's radiator and look for any leaks.
- Faulty heater core: A faulty heater core can also cause coolant to leak into the vehicle's cabin, leading to fogging and a bad odor. If you suspect that your heater core is faulty, you should take your vehicle to a mechanic for diagnosis and repair.
- Clogged cabin air filter: A clogged cabin air filter can restrict the flow of fresh air into the vehicle's cabin, causing the air to become stale and humid, which can lead to fogging and a bad odor. Replace the cabin air filter according to the manufacturer's recommendations.
- Mold or mildew: Mold or mildew can grow in damp, dark areas of your vehicle's interior, such as under the seats or behind the dashboard. This can cause a musty odor and can also contribute to fogging. To prevent mold and mildew growth, keep your vehicle clean and dry, and use a dehumidifier if necessary.
If you are unable to identify the source of the fogging and bad odor yourself, you should take your vehicle to a mechanic for diagnosis and repair.
