"Stacy's Mom". This prompted Ric Ocasek to say the opening was a sample; however, the band has insisted they "got it right". Release "Just What I Needed" was released as a single in 1978 prior to the release of The Cars, backed with "I'm in Touch with Your World". The song peaked at number 27 on the US Billboard Hot 100 and number 17 on the UK Singles Chart, as well as number 38 in New Zealand. The single was the Cars' most successful of the songs on The Cars in the United States, with follow-up singles "My Best Friend's Girl" and "Good Times Roll" charting at numbers 35 and 41, respectively. "Just What I Needed" appeared on multiple compilation albums, among them being Greatest Hits, Just What I Needed: The Cars Anthology, Shake It Up & Other Hits, Complete Greatest Hits, The Essentials, and Classic Tracks. It appeared on the soundtracks for the films Boys Don’t Cry, Over the Edge and 200 Cigarettes. The song was also featured in an advertising campaign by Circuit City in 2004. "Just What I Needed" has since been covered by several artists, including by the Strokes with Jarvis Cocker in 2011, the Killers in 2018, and the Red Hot Chili Peppers in 2019. Reception AllMusic reviewer Donald A. Guarisco praised it as "a clever pop song", commenting that "Elliot Easton's fiery guitar leads duel with Greg Hawkes' icy synth lines over a throbbing pop/rock backbeat while Benjamin Orr lays down a fey, detached vocal that captures the sarcastic edge of the lyrics with skill." Billboard said that it was energized by a "driving, propulsive beat" and enhanced by "feisty rock guitar lines" and "a winning harmonic vocal style." Cash Box said that "the ticking guitar opening is reminiscent of Tommy James & The Shondells and that "the tight-lick guitar work and excellent singing" make it likely to go to the top of pop music playlists. Record World said that "Roy Thomas Baker's production and the group's lively vocals makes the record a standout." Rolling Stone named the song one of Ocasek's "essential songs", praising the "chugging eighth-note guitars marching along in crisp perfection" in the song. Ultimate Classic Rock named the song the best Cars song as well as the best Benjamin Orr Cars song, saying "On a near-perfect debut album, the Roy Thomas Baker-produced "Just What I Needed" was a near-perfect song."