The band originally formed in 1984 from the ashes of the Derry Hitmakers, Bam Bam and the Calling and The Undertones. It was formed by guitarist John O'Neill and second guitarist Raymond Gorman who DJ'd together at the Derry 'Left Bank' club. Drummer and friend Ciaran McLaughlin joined next after having relocated from Derry to London, followed by John's brother and Undertones lead guitarist Damian O'Neill who played bass from 1985 until 1988 upon John's departure. He then took up guitar duties from 1988–1994 and 2008–present. Charismatic American singer Steve Mack, who was on a year out working in a pizzeria in London at the time, finished off the line up. Two more bassists played in the band after John O'Neill left: John Marchini (1988–1991) then Brendan Kelly (1991–1994 and 2008–present). That Petrol Emotion's influences encompassed artists as diverse as The Beatles, Afrika Bambaataa, Television, Sly & the Family Stone, Captain Beefheart and Can.