In April 2011, SpaceX was planning for a first launch of Falcon Heavy from Vandenberg Air Force Base on the West Coast in 2013. It refurbished Launch Complex 4E at Vandenberg AFB to accommodate Falcon 9 and Heavy. The first launch from the Cape Canaveral East Coast launch complex was planned for late 2013 or 2014.
Due partly to the failure of SpaceX CRS-7 in June 2015, SpaceX rescheduled the maiden Falcon Heavy flight in September 2015 to occur no earlier than April 2016, but by February 2016 had postponed it again to late 2016. The flight was to be launched from the refurbished Kennedy Space Center Launch Complex 39A.
In August 2016, the demonstration flight was moved to early 2017, then to summer 2017, to late 2017 and to January 2018.
At a July 2017 meeting of the International Space Station Research and Development meeting in Washington, D.C., SpaceX CEO Elon Musk downplayed expectations for the success of the maiden flight:
There's a real good chance the vehicle won't make it to orbit ... I hope it makes it far enough away from the pad that it does not cause pad damage. I would consider even that a win, to be honest.
Musk went on to say the integration and structural challenges of combining three Falcon 9 cores were much more difficult than expected. The plan was for all three cores to land back on Earth after launch.
In December 2017, Musk tweeted that the dummy payload on the maiden Falcon Heavy launch would be his personal midnight cherry Tesla Roadster playing David Bowie's "Life on Mars", and that it would be launched into an orbit around the Sun that will take it as far out as Mars' orbit. He released pictures in the following days. The car has three cameras attached that provided "epic views".
On December 28, 2017, the Falcon Heavy was moved to the launch pad in preparation of a static fire test of all 27 engines, which was expected on January 19, 2018. However, due to the U.S. government shutdown that began on January 20, the testing and launch were further delayed.
The static fire test was conducted on January 24, 2018. Musk confirmed via that the test "was good" and announced the rocket would be launched in approximately one week.