Smoke Testing
WARNING: This page is about a different car, the 2018 Jaguar XF. However, it is still accessible from the selected car via links, so may be relevant.
Smoke testing should be used to identify a leak only when instructed by Dealer Technical Support. Refer to the manufacturer's instructions for information regarding using the smoke test equipment. Smoke may be introduced into the fuel system via the purge hose, the fuel filler neck or the DMTL filter housing. When introducing smoke via the DMTL filter housing, use the manufacturer approved diagnostic system to perform routine - Evaporative System Diagnostic Check - to ensure that the DMTL changeover valve is energized and the DMTL pump is running.