WINDSOR — Three people who police believe died of carbon monoxide poisoning while driving off-road may have taken steps to get the fresh air that would have saved their lives.

A Windsor couple, Reginald “Skip” Gay, 41, and his wife, Samantha Davis-Gay, 33, and a friend, Luke Thompson, 22, of China, were found dead Saturday night in a Jeep Wrangler. Investigators believe the Jeep got stuck in a bog and continual revving created excessive exhaust.

Carbon monoxide is odorless and tasteless, so the only warning would have been unpleasant exhaust fumes.

Capt. Daniel Davies of the Kennebec County Sheriff’s Office said alcohol may have been a factor in the deaths. He confirmed that a cooler in the Jeep contained alcoholic beverages.

Davies said there is evidence the three opened the windows to vent the hard-top Jeep. Reginald Gay gunned the V-8 engine to try to crawl out of the muck hole, spraying the side of the vehicle with mud. Investigators found no mud in the Jeep, however.

“That indicates the windows were up,” Davies said. “We’re not sure when they were rolled down, but even with the windows down, under these circumstances — in a ravine, with no breeze — there’s no air exchange.”

A spokesman for the state Medical Examiner’s Office said Monday that the cause of death cannot be verified until blood tests are concluded, which may take several weeks.