There are a few reasons your cars heater could smell bad and a dirty Cabin Air Filter could be one of them. It is the Cabin Air Filters job to clean the air coming into the car. Over time the Cabin Air Filter starts to fill up with debris. Sometimes the filter gets clogged a little faster because mice find it to be a great place to make a home. In the picture above that is exactly what happened. When the mouse made his home on top of the filter he peed on it, causing the cars heater to smell bad. Regularly checking and replacing your cars cabin air filter can help avoid issues like this one. We at King’s Auto Repair suggest having your Cabin Air Filter Checked every 6 Months and replaced as necessary. Call us today and we can help track down that bad smell from your heater.