Balelo, a 40-year-old reality TV personality, was found dead Monday in his car, which was parked with the engine running in the garage of his business in Simi Valley, Calif.
E! News said an autopsy indicated Balelo died of carbon monoxide poisoning and the death has been ruled a suicide.
"We are deeply saddened by this tragedy and our thoughts are with Mark's family," A&E, the cable network that airs "Storage Wars," said in a statement to E! News.
Balelo's death followed his arrest Saturday for suspicion of possessing a controlled substance.
Balelo was known for wearing flashy clothes to auctions on "Storage Wars," a series that follows people who buy the contents of unpaid storage units as single lots, then try to resell items for profit. The show debuted in 2010.