While a car is sitting (or floating) in a flood, the water carries in all manner of debris, such as grass, dirt, sand and silt. When the water level recedes, the water itself may be gone, but much of the debris remains. It's difficult for someone cleaning a car to remove all of it.
When examining a used car, you'll want to look in the places where mud and grass may remain after a flood. These include the following areas:
- inside and under the glove compartment
- engine crevices
- the trunk
- under the spare tire
- under the dashboard
- below seats and in seating tracks
- in wheel wells
- around wiring
If you do find debris in these areas, the car may have been sitting in water for a while.