The truck, a 1991 Dodge pickup, has since been found abandoned at Pine Street and 13th Avenue — but there was no sign of three-year-old Tzou.
Owner Kristyn Christiansen believes the dog was let out of the truck at that intersection, in the area where Fairview meets Kitsilano and Shaughnessy.
He says his dog is hard to miss, and very approachable.
"He's huge," Christansen said. "He's a very playful dog. He's very friendly. He'll go up to anybody. He's not really afraid of people or other animals."
Christiansen said he regrets the lapse in judgment he made when he parked on Keefer Street near Gore Avenue and went across the street to the bank, leaving the keys in the ignition.
He wasn't gone long — maybe 40 seconds — and he didn't hear his truck's loud engine starting up.
"My first instinct was 'am I losing my mind, my vehicle's not here,'" he said.
Christiansen calls Tzou "my kid," and says he desperately wants him back.
"I feel strong that he's OK... that somebody's taking care of him," he said. "Hopefully, they will find it upon themselves to turn him in, and return him to his rightful home."
Anyone with information on the missing dog can call animal control at 604-781-6888.