Warnock was taking charge of his third game since replacing Simon Grayson at the end of last month, but there was little evidence his latest club can mount a late play-off challenge in the Championship.
Hull will feel they created enough first-half chances to clinch their first win over Leeds in six attempts, but were thwarted on several occasions by the visitors' inspired goalkeeper Andy Lonergan.
The point has done little to boost Hull's own play-off hopes and having now drawn four of their last five league matches they have lost further ground on their nearest rivals.
Leeds came more into the contest in the second half, but were short on quality in the final third, while Nick Barmby's Tigers are unbeaten in eight games, but have scored only one goal in their last four encounters.
Hull made just one change to their starting line-up, with Corry Evans back in midfield in place of Seyi Olofinjana, while Paul Connolly returned for Leeds and latest loan signing Danny Webber made his full debut.
Leeds set the early pace and threatened in the third minute when striker Luciano Becchio fired an angled shot over the crossbar and Roberts Snodgrass volleyed wide from 20 yards soon after.
Hull had to wait until the 23rd minute before their first serious attempt on goal, with winger Cameron Stewart's angled effort fizzing over before Robert Koren's 30-yard curler was comfortably held by Lonergan.
Both sides created plenty of first-half chances. Becchio's header was well held by Hull goalkeeper Vito Mannone and Koren forced a fine save from Lonergan with a right-footed volley from the edge of the penalty area.
Hull moved through the gears towards the interval with Lonergan twice coming to Leeds' rescue, pulling off superb saves to keep out Evans' angled drive and then Stewart's blistering effort as the home side finished the first half well on top.
Mclean blazed a shot from the edge of the area over the crossbar soon after the restart, but Leeds stemmed the tide and Snodgrass - who swapped wings having been well-marshalled by Andy Dawson in the first half - dragged a shot wide.
But although Leeds wrestled back a bigger share of possession they were quickly closed down and let themselves down with a poor final ball.
Ross McCormack was caught in two minds when well-placed in the area in the 68th minute and his cross-shot was caught by Mannone and Adam Clayton's thumping shot was blocked by Hull substitute Josh King following McCormack's free-kick.
Leeds boss Warnock sent on Lloyd Sam for Webber in the 77th minute and Mark Cullen replaced Hull winger Stewart, but neither side went close to breaking the deadlock in the closing stages.