The US champion, along with Belgian Lotte Kopecky, caught the leading duo of Dutch great Marianne Vos and Hungarian Blanka Vas with 3.4km remaining and immediately produced a brutal acceleration.
Vas, Vos and Kopecky looked at each other, all three reluctant to burn the little energy they had left to chase and let Faulkner ride to glory by the Eiffel Tower.
She seemed in such disbelief that despite her comfortable advantage on the Pont d'Iena, she did not even celebrate as she crossed the finish line.
"It's a dream come true," Faulkner said.
"I knew Kopecky wanted to catch the front two so I knew she'd ride with me and I also knew if we caught them I had to attack because I could not beat them at the line."
Vos won the three-women sprint to take silver and Kopecky claimed the bronze.
"We managed to bridge the gap (with Vas and Vos) and we all looked at each other," world champion Kopecky told reporters.
"On paper, Marianne was the fastest sprinter so it made me think and I did not want to make the effort. So I focused on getting a medal."
The first decisive moment came when American Chloe Dygert crashed on a corner just before the Butte Montmartre climb, causing a bunch split.
Kopecky was on the wrong side of it but she managed to fight her way back in the descent before Vos and Vas pulled away.
Belgium coach Ludwig Willem justified Kopecky's risk-averse strategy.
"It is indeed a poker game, you keep an eye on one another," he told reporters.
"One cannot say she played it badly. At this level, one is fighting for an Olympic title, one has to take risks, and you can end up with bronze instead of gold, but she also could have ended up in fourth position."
For Vos, a 14-time world champion across four cycling disciplines, it was a missed opportunity to add to her London 2012 road race title and 2008 Beijing points race gold medal on the track.