On a day dominated by Mario Balotelli's expected move to AC Milan, Roberto Mancini's side could have done with a moment of magic from the Italy international.
Defensive heroics from the hosts and the fine form of Julio Cesar denied City in west London, leaving them four points behind rivals United.
That gap could extend to seven points should Sir Alex Ferguson's side beat Southampton on Wednesday night, and City will be kicking themselves for failing to make it five successive league wins on Tuesday evening.
Pablo Zabaleta hit the crossbar and Cesar superbly denied Gareth Barry in a first half in which Adel Taarabt was superbly denied by Joe Hart.
January acquisition Loic Remy was lucky to avoid a booking for a dive after the break as QPR spent most the second half on the back foot, successful withstanding a barrage of City attacks.
The match got off to a tentative start on a wet and windy evening in west London.
QPR, showing eight changes following their embarrassing defeat to MK Dons, seemed happy to sit back and soak up Manchester City pressure, with the hope of catching them on the break.
It was a dangerous ploy and one that threatened to catch them out on a number of occasions during the opening 20 minutes.
The home side's Nedum Onuoha, a graduate of the City academy, did well to clear away a threatening Samir Nasri cross, before Shaun Derry threw himself in front of a Sergio Aguero strike.
Joleon Lescott volleyed over after QPR goalkeeper Cesar failed to deal with a David Silva corner.
The Brazilian shot-stopper was quick to make amends, though, preventing Ryan Nelsen deflecting a James Milner shot into his own goal.
Clint Hill cleared a low Aguero cross that look set to be turned in as Mancini's men continued to press for an opener.
That attacking impetus saw Silva send over a delicate dinked cross, which Zabaleta met with a powerful header that rattled the bar.
Javi Garcia, playing as a makeshift centre-back alongside Lescott, then saw an audacious 45-yard half-volley whistle just wide, before he was called into action at the other end.
Remy latched onto a quickly-taken Stephane Mbia free-kick and fired a low strike from an acute angle that would have tested Hart had it not been for a deflection off the Spaniard's heel.
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QPR were starting to get more joy on the break and, after Aguero saw a goal ruled out for offside, Taarabt went close to breaking the deadlock.
The Moroccan playmaker burst forward and a stepover easily took him past Gael Clichy, only to see his goalbound strike superbly denied by Hart, making his 150th league start for City.
After Mbia became the first player booked, the visitors returned to the attack and would have had the opener had Cesar not been alert to keep out a fine left-footed Barry strike, with Nasri striking wide just before the break.
The match was more even when play resumed and Taarabt saw a strike deflected behind by Lescott.
Silva was lucky not to be reprimanded by referee Phil Dowd after kicking out at Derry off the ball, before Esteban Granero was harshly booked for a challenge on Silva.
Mancini brought on Edin Dzeko in search of a winner but it was QPR that were next to have a chance, with Remy curling wide.
The change was soon having an impact as City attacking with renewed vigour.
Cesar denied Silva after a neat one-two with Carlos Tevez, before Dzeko nodded over from a corner and Aguero mis-hit a Zabaleta cutback.
Milner was next to get a shot away for City, moments after Remy saw penalty appeals waved away.
The France international appeared to dive under pressure from Lescott and play soon returned to the other end.
Cesar somehow kept out Silva from a Dzeko cross, before the Spaniard saw a fierce drive thwarted by Nelsen.
The City midfielder was finding himself in the heart of the action and claimed for a penalty against Onuoha towards the end, although Dowd deemed the defender to have won the ball.
There was to be no City winner, though, and QPR's players gave Nelsen a guard of honour on what was his final game for the club before taking over as Toronto FC head coach.