The Greatest Miracle is the eighth episode of Engine Sentai Go-Onger.
The giant Boring Banki attacks the city until the Go-ongers arrive, letting Carrigator rest due his massive recharging as the primary Go-ongers attempt to use Speedor and the others. However, the primary Go-ongers learn their Engine partners are unable to enlarge due to Bombe Banki's attack. Then, Boring Banki burrows its drill underground and enters a sleep mode. By then, the Pollution Ministers arrive to take out the Go-ongers personally with the Engines disposed of, defeating them easily with their barrier attack. Later, after an attempt of removing the rust with a miracle and Speedor not being as confident, an upset Sōsuke runs off until he receives aid from his racing coach: Tojiro Fuji. Seeing that Sōsuke still the same as he was, a miracle maker who acts on his own, Tojiro reminds him that even heroes need the support of others. Sōsuke finds Speedor, who almost got himself kill to find his human. Though Sōsuke apologizes for his actions, Speedor stays the true miracle was their meeting. As Sōsuke resumes de-rusting Speedor, Gunpei and Hant learn that Boring Banki plans to drill into a magma chamber below the city in order to destroy it in an eruption. The two transform to fight the Pollution Ministers before Go-on Blue and Go-on Yellow arrive after restoring their Engines to cover the two as they form GunBir-O to stop Boring Banki, only to overpowered by the stronger opponent due to Carrigator not being at full power. But at the last second, Sōsuke arrives with a fully restored Speedor. Using the Highway Buster three times, the Go-ongers take out the Pollution Ministers' barrier before forming Engine-Oh to support GunBir-O. Together, Engine-Oh and GunBir-O scrap Boring Banki with their attacks as Tojiro watches in pride of Sōsuke's miracle coming true.