My truck is well maintained and has 144,000 miles. Recently it periodically drops to idle while at normal driving speeds ranging from 45 to 75 mph. Pop into neutral, say a quick prayer (ATL traffic!), switch key off/start, she cranks for a second then fires up and drives just fine for another few hundred miles. No check engine light, no codes in the OBD. First time it did show a wrench icon, there was some sort of throttle body code but I had that replaced by Ford 2 years ago. Also got a new engine wiring harness, alternator, and computer 9 months ago after either wire insulation degrading or rodents killed it.