I have a 2012 XLT four-wheel-drive. Long bed with a 36 gallon fuel tank. 96,000 miles. Just had a tuneup done less than 1000 miles ago. Truck has been intermittently not starting. The engine will crank with the starter plenty of battery power. But it won't turn over. Seems to not be getting any fuel. Changed the fuel pump relay and the truck started. However, it was a fluke. I'm back to it not starting. I'm hoping it's not the fuel pump. When the truck starts there's no indication of a fuel supply problem. No stuttering or jerkiness. Any other ideas?