On Thursday, Stintz endorsed Christin Carmichael Greb, a candidate she said she met for the first time earlier this year.
"She came to see me and expressed her interest in running for council and since that time, she's become very knowledgeable about the issues, she's built a strong team, she has campaigned across the entire ward and she has earned my confidence as someone who understands the issues of the community and can best represent the community that I live in at city hall," said Stintz, who said she had put a sign for Carmichael Greb on her lawn.
Stintz said she had told all the candidates in the ward that she "wasn't going to get involved," but she changed her mind.
"That was my intention, but as we get closer to the polls, I felt compelled to come out and express my support for Christin," she said.
Carmichael Greb thanked Stintz for her service as a councillor and told reporters that she was "honoured to have her endorsement."
'I never sought Karen's endorsement'
Stintz is not endorsing Jean-Pierre Boutros, who previously served as her policy adviser.
Asked why she picked Carmichael Greb over Boutros, Stintz did not directly refer to him in answering the question.
"Since meeting Christin, she has my full confidence that she best understands the issues of our community and can best represent our community at city hall," Stintz said.
Boutros told reporters Thursday he had not been expecting an endorsement from his former boss.
"I never sought Karen's endorsement, nor did she seek mine, so there was always that understanding," Boutros said.
He said "all of Christin's support is based on pro-development, pro-subway [and] special interests."
Boutros said Carmichael Greb's interests "align more with developers and Conservative bagmen in Ottawa than they do the community and I'm here to protect that."
'Supportive of the expansion'
Carmichael Greb was asked a question about her position on the Scarborough subway.
"This is about local issues," she said, without answering the subway question.
Carmichael Greb then confirmed to reporters that she works in project management at Bombardier Aerospace, though she is on a leave of absence at the moment.
She was then asked her position on the proposed expansion of Toronto's island airport. Bombardier makes some of the aircraft that currently fly out of the island, while another of its divisions has built transit vehicles for the TTC.
"My position has nothing to do with where I work, I'm supportive of the expansion, pending the environmental assessment … but it has nothing to do with where I work or where I’ve been in my past," Carmichael Greb said.
Carmichael Greb was also asked if she would be able to vote on airport expansion, should she be elected as the councillor.
"My position at where I work has nothing to work with what my views are and what's best for the city and what's best for Ward 16," she said, noting that she would not continue to work at Bombardier if elected.
Stintz's nod for Carmichael Greb wasn’t the only endorsement she made this week.
A day earlier, she endorsed Jennifer McKelvie, a candidate seeking to become the councillor in Ward 44 Scarborough East.
Stintz has served as the councillor in Ward 16 Eglinton-Lawrence for three terms. She made a run for mayor, but withdrew from the race in August.