Report By FootyMAD
Reading battled back from a goal down to hand Kevin Dillon his first success as caretaker manager.
Dillon, who stepped into the void after Alan Pardew resigned last week, looked to be heading for a second straight defeat in a week of turmoil as Peter Thorne gave Cardiff a 12th minute lead.
But whatever stand-in boss Dillon said at half time did his team - and his chances of the job on a full time basis a power of good.
The home side responded superbly in the second half and were deservedly back on level terms due to Nicky Forster's first league goal of the season.
And the outstanding Steven Sidwell capped the Reading fightback with a stunning winner 11 minutes from time that prompted an emotional dance on the Madejski Stadium pitch from Dillon.
A tense first week in the job for Dillon had seen Reading beaten for the first time this season when they faced a West Ham side expected to confirm Pardew as their new manager in the coming weeks.
And Cardiff looked likely to make it back-to-back defeats for the new man in charge as they deservedly took a first-half lead.
Thorne, who celebrated his start to the season with a goal repeated the trick with a cool finish from a Graham Kavanagh pass on twelve minutes.
Cardiff might have had a second five minutes before half time but were denied by a superb Marcus Hahnemann block from a Robert Earnshaw shot.
Reading sensed a way back and probed for an equaliser in a much-improved half, deservedly finding a breakthrough just after the hour mark.
Winger Scott Murray was the provider with a low shot that fell kindly for Forster, who gratefully turned in from close range.
Reading, prompted by the superb performance of England Under-21 star Sidwell, went in search of the winner and lively Cardiff were gradually worn down.
Sidwell had already gone close with a vicious left-foot volley following a Murray corner early in the second half but he was not to be denied when he sensed another opportunity 11 minutes from time.
A neat Reading build up ended when Andrew Hughes rolled a ball out wide to the dangerous Murray and his cut back found Sidwell in space and allowed the young midfielder to let fly into the top left hand corner.