Coun. Paul Ainslie tweeted that residents in his ward started getting calls Friday night with a minute-long recorded message from Ford.
In the recording, Ford says it was "extremely unfortunate" Ainslie did not vote in favour a subway extension in the councillor's east Toronto ward earlier this week.
Ainslie says he resigned from the executive committee because he didn't want to be "bullied" by the mayor and told how to vote.
Ainslie got a verbal lashing from Ford and his councillor brother Doug Ford this week after he led a motion to build a cheaper light-rail line instead of a subway, a move that was shot down in council.
Several councillors took to Twitter to criticize the robocalls, with one suggesting the city's integrity watchdog should look into the matter.
"Integrity Commissioner will need a copy," Coun. Kristyn Wong-Tam posted.
"All Cllrs should be against Rob's robocall. Tweet YOUR Cllr if they're on twitter whether 4 or against subway, the call is wrong," tweeted Coun. Shelley Carroll.
In the recording, which has been posted online, Ford singles out Ainslie from his fellow east-end councillors for his subway stance.
"It was extremely, extremely unfortunate that your councillor Paul Ainslie was the only Scarborough councillor who did not listen to his constituents and voted against the Scarborough subway," Ford said in his message.
He added Ainslie's views on the issue were behind his departure from the executive committee.
"We are moving forward with a team who support the mandate Toronto taxpayers gave me. Please have a safe and enjoyable Thanksgiving," the audio statement ends.
(The Canadian Press, CFRB)