Description And Operation: Description: Notes
WARNING: This page is about a different car, the 2017 Kia Niro. However, it is still accessible from the selected car via links, so may be relevant.
NVLD (Natural Vacuum Leakage Detection) is located between the canister and the fuel tank air filter. NVLD is to detect leaks equivalent to a 0.5 mm hole in the fuel tank, canister and hoses. When the engine has been running, the temperature of the fuel in the fuel tank is raised slightly. When the engine is shut off, the temperature of the fuel should drop. The ideal gas law states that in a sealed system the pressure drops proportionately to a drop in temperature.