Odd noise

[Crickleymal]

Hi all. 2008 Estima Aeras 2.4 non hybrid 

I have an odd noise which I only notice when sitting in the car with the engine off. At first I thought it was someone operating a road drill a couple of streets away. It only happens once every 5 or 10 minutes and lasts for no more than a second. It does sound like a very quiet road drill or a burp.

 

I'm not overly concerned about it. I assume it's probably something to do with air seeping into the fuel tank or something as I hear a hiss when I remove the filler cap at a petrol station.

[JohnGW]

Fuel tanks often hiss when you relase the cap, nothing unusual there. You say with the engine off but electrics?

[Crickleymal]

Everything off. Electrics as well. It's impossible to record as the time it occurs is random.

[Paulscarbs]

There are many electrical components within the vehicle. Some remain active even when the ignition is off. I would suggest it is a solenoid or something similar.

You may, if your radio doesn’t have an unknown code, wish to disconnect the Battery and see if the noise persists.