Wolves took a first-half lead thanks to Leon Clarke's header but were pegged back when Gary McSheffrey converted the penalty he won from Lee Naylor's foul.
With just over 10 minutes left, Naylor looked to have made up for his error when his shot deflected off Steve Staunton and past Luke Steele.
But Stern John's determined run and finish condemned Wolves to their 22nd draw of the season.
Wolves boss Glenn Hoddle:
"It was a stupid mistake by Ki-HyeonSeol which cost us.
"I praise him highly when he does well, but he's got to learn he can't play flicky-flicky football at that time in the game and in that position.
"We've given the ball away in a dangerous position and conceded a goal which should never have happened."
Coventry: Steele, Duffy, Page, Staunton, Hall, McSheffrey, Jorgensen (Benjamin 82), Doyle, Dyer (Morrell 74), Adebola, Goater (John 66).
Subs Not Used: Pressman, Whing.
Goals: McSheffrey 19 pen, John 90.
Wolverhampton: Oakes, Bischoff, Lescott, Craddock, Naylor, Cameron (Kennedy 83), Ince, Olofinjana, Seol, Miller, Clarke (Ricketts 89).
Subs Not Used: Edwards, Cooper, Clingan.
Goals: Clarke 15, Naylor 79.
Ref: G Hegley (Hertfordshire).