I have a 2005 Ranger, 4.0L V6 SOHC, manual, 4x4, 22155 miles.

For the second time now, the engine has lost power and died. The first time, I heard a low "pop" from under the hood and the engine died about 5 mins later. I tried to restart it about 5 times over the span of 45 minutes with no luck, although the starter operated at full power. I had to have it towed to the ford dealer and the next morning it started right up and worked fine when the mechanic took it out to test drive it. Ultimately, the mechanics couldn't get it to repeat what it did to me, and gave it back to me without making any repairs.

After 150 miles of flawless operation, the engine lost power and died again without any unusual noise from under the hood. Just like the last time, I could not restart it. But after 10 minutes it started up and I was able to drive it back to the ford dealer.

I should say too that I am pretty sure I felt the engine lose power for a second or two several days before before both of the times it actually died.

I am pretty sure this is a fuel system problem, but what should I tell the service dept. to look for?