I have a 2011 Ford F-150 with the V6 Ecoboost. It has 108,000 miles on it. Recently it's been starting rough the first time. It starts fine but makes a weird rumbling sound afterward like the starter is loose or something. However, when I ran errands the rest of the day and started and stopped it, it started fine. So I was thinking it had to do with something perhaps being loose and once the engine is hot and everything expands it tightens up and doesn't have that problem any more.

This problem only seems to happen when the truck has been sitting for over 8 hours.


What could the problem be?