"Snap" sound from LPG tank?

Especially when I start my car, there is a voice that says "snap" by the luggage on the back (my car is a station wagon, so a sound that can come from the tank can easily come to my ear). as if I hit a metal plate with my fingernail. Then it doesn't happen again. But when I run almost every vehicle, this sounds. I wonder if a piece in the tank hits the tank when the vehicle is running? why could it be?

your vehicle is switching to lpg :)

Exactly :) After running the sequential system, a click sound is heard.

It comes from the LPG tank, activates the gas, there is nothing to be afraid of.

The solenoid valves, which are located in the tank and in the engine room for the safety of LPG, may come to the gas engine. It's normal to hear this sound.

Hmm. understood :) I was not hearing in the previous vehicle because the tank was in spare wheel ..