Piston

Piston was a deceased character that Diesel killed him before the events of A Car's Life: Sparky's Big Adventure.

Trivia

 * He was the only character in the film to have any deaths mentioned.
 * The only visible part left was his abandoned hubcap, which is actually the same as Diesel's hubcaps.
 * "Rust in Peace" is a play on "Rest in Peace".