Bellagio fountains analogy
Let me add another analogy to this morass of speculation with respect to fuel freezing, pressure changes, etc.
If memory serves me correctly, there was a Discovery Channel show some years back concerning problems with the "dancing" fountains installed in front of the Bellagio Hotel in Las Vegas.
These fountains consisted of numerous jets that would spew out high pressure streams of water as commanded by a set of computer-controlled solenoid valves. To create their "dancing" effects in concert with music programs, the solenoids would very rapidly switch the individual jets on and off.
Almost immediately, this system began to have problems as the solenoids would cycle, but water would only intermittantly spew out of the fountain jet. When technicians would examine the valves, which were located at the bottom of the fountain pool, they would find no problem. Finally, someone had the wit to speculate that the rapid pressure drop from an opening of the solenoid valve was causing water to freeze in the line. But by the time the technician reached the valve to inspect it, Las Vegas' >40 degree C. summer heat had caused the ice plug to thaw and disappear.
I can't recall exactly the fix -- whether to slow down the solenoid actuation speed -- or something else. But the problem was eliminated and the fountains have become a major tourist attraction.