Leeds threw away a three-goal lead and the chance to go back to the top of table, above West Brom, who won earlier in the day at Birmingham as they were held to a draw by Cardiff.
Leeds had taken a firm grip on the game when Helder Costa and Patrick Bamford scored within the first eight minutes and they looked to be cruising when Bamford converted a penalty that he had won seven minutes into the second half.
Lee Tomlin pulled a goal back after 60 minutes but a Leeds win still looked secure.
Sean Morrison pulled another back with eight minutes to go before he was sent off for violent conduct four minutes later. But the 10 men of Cardiff shrugged off this setback and pulled level through Robert Glatzel with two minutes to go.
Leeds started strongly with Pablo Hernández shooting wide inside the first minute. They soon got their reward when Costa fired in off the post after Hernández’s long ball picked him out following a swift counterattack after six minutes.
It got even better for the home side two minutes later when Bamford doubled their lead after getting on the end of a Stuart Dallas cross.
Cardiff survived penalty shouts after 24 minutes when Joe Bennett appeared to bring down Costa. Bamford blazed a dangerous free-kick well over after 28 minutes before Nathan Mendez-Laing curled wide two minutes later.
Luke Ayling fired over soon after the restart as Leeds showed no sign of letting up in the second 45 minutes and it was 3-0 after 52 minutes when Bamford slotted home from the spot after he had been fouled by Neil Etheridge.
It was nearly 4-0 two minutes later when Etheridge did well to keep put Mateusz Klich’s header.
Tomlin pulled a goal back on the hour when he lifted the ball into an empty net after Kiko Casilla messed up a cross. It was the first goal Leeds had conceded in five games.
Morrison then headed home after 82 minutes from Bennett’s cross as Cardiff set up a tense finish, but four minutes later he was sent off for a lunge on Eddie Nketiah.
Cardiff then levelled after 88 minutes when Glatzel slotted home after Pascal Struijk failed to clear his lines.
The Leeds manager, Marcelo Bielsa, could not explain how his side threw away a three-goal lead. “I did not get the preparation right because I knew about Cardiff City’s strengths and we didn’t resolve it,” he said. “We knew how dangerous they are in the air and from set-pieces. Set-pieces are crucial in this division and Cardiff made us pay in that area.
“Some of our attacking play was the best I have seen from Leeds and it is difficult to explain the result.
“ There is no way we should have drawn that game. l felt the substitutes were OK, we needed to take Bamford off to freshen things up a bit.
“We wanted to give Stuart Dallas more help down the left and to get more height out on the pitch.
“I don’t look back on the subs and think I got it wrong. I felt that we were defending OK and even at 3-2 the team was calm.
“Defensively we were not that bad, but they have exploited us for the third goal.”
Neil Harris hailed Cardiff’s ability to hang in there.
“Leeds are a great side, the energy they have, the ability they have and the forward runs they have make them a great side,” he said.
“They are as one of the best sides I have seen in the Championship in years.
“They were better than us, but we gave them a leg up, we gave poor goals away and their penalty was debatable.
“ The boys have shown great character to come from behind, but we cannot give good teams a start and shoot ourselves in the foot.
“We got off to a bad start, Leeds are very dangerous on the counterattack and we did not box off the edge of the box as well as we should have done.
“Lee Tomlin’s goal was a brilliant finish, he has got great ability and that moment got us back into it.
“I have got 11 points from my six games in charge so I am really pleased with that return.
“The message is getting across and the confidence is growing.”