This should be an easy one for those in the know (not me)
While washing my 2018 XLT I kept hearing a noise. Sounding very much like a camera shutter and then automatic film advance. I know it wasn't. lt happened several times. The pickup was not running. What was it?

 

Were you opening the driver's side door when you'd hear the noise? Think I've read elsewhere on this forum that it's the electric fuel pump pressuring the system. I know I hear it when I open the driver door. Then again I could be 100% wrong about that....

 

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If you are correct, and I sure don't know, that will be interesting. When I heard it for the first time, the salesman said it was the tail gate unlocking.

 

Well, the doors were open, but I've heard it other times as well after I close the doors. But you may be on to something, it's a sound I can see from the fuel pump pressurizing the system.

 

I believe I've figured this one out. It's the grill shutters. I don't know why they are cycling with the key off, but while washing the front with an ear close to that area it certainly appears the noise is the shutters.