A testing device for a vehicle part having an interior space is disclosed. The testing device includes a conduit, a test material source, and a controller. The conduit includes a first end and a second end, the first end operable to be disposed within the interior space of the vehicle part and the second end operable to be disposed outside the vehicle part. The test material source is in fluid communication with the conduit to provide a test material to the conduit. The controller is configured to direct the test material from the test material source through the conduit to the interior space in a predetermined manner.