The Speed Demon is a ghost from The Real Ghostbusters Magazine Summer 1989 story "The Speed Demon".
The Speed Demon was haunting the New York Grand Prix race track, causing much destruction to the racecourse. The Ghostbusters were called to capture the spook, and had the formula ones equipped with proton packs and ghost traps. The Speed Demon gave the Ghostbusters a little trouble in the "race", then took control of the Ecto-1. The ghost didn't notice Ray, who had been taking a nap in the Ecto-1, and was then caught in a ghost trap.