Late goals from defender Calum Davenport and substitute Jay Bothroyd saw Coventry come from behind to maintain their unbeaten start to their Nationwide Division One campaign and inflict Reading's first home defeat of 2002.
Jamie Cureton put Reading ahead from the penalty spot after 13 minutes but his third goal in two starts this season was not enough for the home side.
Substitute Bothroyd struck with eight minutes left to seal a late fightback by Gary McAllister's Coventry.
Reading had looked to be heading for a second successive victory when Cureton struck but Coventry came from behind for the second successive Saturday as two goals in eight minutes maintained their unbeaten start to the season.
Reading made a blistering start in heat to match and made the break through after 13 minutes.
Sam Igoe's fierce near post shot was pushed away by Morten Hyldgaard but from the resulting corner, veteran defender Richard Shaw inexplicably handled as three Coventry defenders went for the same ball.
Cureton gratefully accepted the gift, beating Hyldgaard from the spot to register his third goal from two starts this season.
Coventry's greatest threat was carried in the shape of striker Lee Hughes, making his first start of the season following a hamstring injury.
The home side nearly doubled their advantage early in the second half when Cureton's flick put Martin Butler clear but the striker was denied again this time by a sharp save from Hyldgaard.
His low stop proved crucial as City forced a late surge, Calum Davenport crashing home a header from substitute Youssef Chippo's free-kick to haul them level 16 minutes from time.
The comeback was completed eight minutes later when David Thompson found Hughes who neatly chested the ball down for substitute Bothroyd to run in behind the Reading defence and slot the ball inside Whitehead's far post