Louanne Kennedy, Northridge's interim president, said the school had reason to dismiss Ponciano, the Big Sky Conference coach of the year in his only season. The Matadors were 7-4 last season.
"I have a preliminary [internal] report now that indicates there are substantial NCAA violations," Kennedy said. "They've been validated to my satisfaction."
As he has done throughout the investigation, Ponciano steadfastly denied wrongdoing and said he is considering legal action. He refused to accept a $43,000 buyout offered by Northridge.
"The things they said I did, I didn't do," Ponciano said. "That's why I didn't resign."