Investigators now believe it was a Mercedes — found in the garage of a home west of Boca Raton — that pumped carbon monoxide into the house, killing two people in their bed earlier this month.
The car has a keyless-ignition system, police say.
The silver Mercedes was found March 1 at the home on Travelers Tree Drive, along with an Acura sedan, the Palm Beach County Sheriff’s Office said. Upstairs, Adele Ridless, 69, and her boyfriend Mort Victor, 79, lay dead in their bed. The house was filled with deadly levels of carbon monoxide, authorities said.
The Sheriff’s Office has not released the make or model of the Mercedes. Investigators impounded the car after discovering the couple’s bodies, and are retrieving data from its computer with the help of the manufacturer, according to a Sheriff’s Office report released Thursday.
They hope to find out when the car’s engine was running and for how long.
Neither car engine was running when deputies were called to the home that evening, but they noticed a strong odor of car exhaust in the house, the report said. The Acura did not have keyless ignition.
Firefighters detected fatal levels of carbon monoxide in the Boca Pointe house, reaching more than 160 parts per million, the report said. Experts say symptoms of poisoning can start at 70 parts per trillion.
Cars with keyless ignition have been linked to carbon monoxide deaths and injuries in at least four states. Critics of the push-button feature say it’s too easy for drivers to forget they left their car running. The invisible, odorless gas often gets trapped in the garage and leaks into an attached house.
A spokeswoman for Mercedes-Benz on Friday declined to comment on local case, but said the Keyless Go feature has been a Mercedes option for more than 10 years. Even with push-button ignition, drivers still can start the car with a regular key, said Donna Boland, a spokeswoman for Mercedes-Benz USA.
“We believe Keyless Go to be a safe system,” Boland wrote in an email. “Nevertheless, as an additional alert, when the driver leaves the vehicle with the ignition on, this triggers a warning chime accompanied by a dashboard message alerting the driver to the situation.”
Fatalities linked to keyless systems from several carmakers have fueled a long-running debate over whether keyless-ignition systems should have stronger warning systems, or even automatic shut-off devices. Some of the systems give audible warnings, but some don’t.
On top of that, not all keyless systems work the same way, so drivers get confused about how to turn off the car, said Paul Green, a professor at the University of Michigan’s Transportation Research Institute.
“I think this is still an open issue,” he said. “There needs to be consistency.”
Ridless and Victor had just returned from dinner at Legal Seafoods in Boca Raton the night before they were found, the Sheriff’s Office report said. Friends told investigators that the pair usually drove the Mercedes when they went out together.
The two had their bags packed to fly the next day from Fort Lauderdale to San Francisco, but they never woke up. Friends came by to pick them up for the airport. They got no answer, and pounded on their door. Using their key, the friends went inside and discovered Ridless and Victor in bed.
A similar carbon monoxide death in suburban Boca Raton in 2010 and other cases have spurred efforts to force carmakers to standardize keyless ignitions and build better warning systems.
Chasity Glisson, 29, died from carbon monoxide poisoning in her townhouse west of Boca Raton in August 2010 after her keyless Lexus ran all night in the garage. Her boyfriend Timothy Maddock nearly died.