The maverick Moroccan was warned by senior players like Shaun Derry and Joey Barton that he was wasting his talent with a lack of application and a poor attitude.
Taarabt, a star of last season's promotion campaign, has been involved in a number of incidents, including walking out of Craven Cottage and catching the bus home as QPR crashed to a 6-0 defeat.
But the 22-year-old is now back in the QPR squad and made an immediate impact off the bench against Sunderland as Warnock's men staged a second-half comeback.
"Adel has trained really well. The lads have got him back in the fold. They have told him why they wanted to kick him in the teeth and he has responded the right way," Warnock said.
"All the lads respected what he did (against Sunderland). Adel did well against Manchester United when he came on."