Fresh from a humbling week in which they exited the EFL Cup to Derby County and lost 3-1 to West Ham in the Premier League, Jose Mourinho's side produced another lifeless display in their second continental game of the season.
A total of just five shots on target being mustered between the two sides over the whole match underlined the lack of attacking quality, with United again unable to get the best out of Alexis Sanchez, restored to the starting line-up after being dropped at the weekend.
The result means the Red Devils are second in Group H, two points behind Juventus and three above third-place Valencia, but the manner of the display will do little to ease the pressure on their under-fire manager, with Marcus Rashford's late free-kick the closest they game to a winner.
4 - Jose Mourinho has gone four consecutive home games in all competitions without a win for the first time in his managerial career. Frustration. pic.twitter.com/hHV9kQ6fSg— OptaJoe (@OptaJoe) October 2, 2018
United started with far greater urgency than they managed against West Ham after kick-off had been delayed due to local traffic problems, but Valencia soon quietened the Old Trafford crowd with some sustained possession and one or two promising breaks down the left from Goncalo Guedes.
Rashford, starting from the left of the United attack, tried two optimistic efforts from range but there was little else of note from the home side in the final third, with Romelu Lukaku managing only one touch of the ball in the Valencia box in the first half.
Paul Pogba stung the palms of goalkeeper Neto with a free-kick as United at last began to increase the pressure in the second half, but a scarcity of any sort of link-up between the front three meant the Brazilian was largely untested.
Valencia were equally unconvincing going forward but Michy Batshuayi wasted a good chance midway through the second half, lashing over on the half-volley following a Francis Coquelin cross.
Lukaku at last came to life with a strong run and shot that Neto saved well to his right, before Mourinho introduced Anthony Martial for the frustrating Sanchez in a bid to spark his attack into life.
Martial won a free-kick from a tight angle from which Rashford clipped the top of the crossbar, before Lukaku headed over when unmarked in the box, but that was as close as the hosts came to ending their winless run.
What it means: United second but Mourinho has little to celebrate
United remain on track for the last 16, but this was a long way from a performance to worry Juventus ahead of their visit after the international break.
It will also do very little to convince critics that their fortunes under Mourinho are going to change quickly, even if this was something of an improvement on their displays last week.
Valencia will certainly be happy with the point – a win over Young Boys on matchday three will keep them very much in the mix to progress to the next round, particularly if United fail to beat group leaders Juve.
Dogged Kondogbia keeps United at bay
Valencia's defence was never unduly stretched by United's forwards, but their task was helped by the towering presence of Geoffrey Kondogbia in midfield.
The former Monaco man harried Pogba whenever his compatriot ventured too far forward, while a number of important interventions in his own box denied the home side a threat from set-pieces.
Valencia given freedom of the flank... by Valencia
Restored to the line-up after missing the West Ham defeat, United captain Antonio Valencia did little to suggest he should be guaranteed a place in the team going forward.
Guedes consistently had time and space to attack down the wing and was not required to do much defending, such was Valencia's reluctance to push up and support Sanchez.
Key Opta stats: United's rare Old Trafford slump
- United are winless in their last four games in all competitions at Old Trafford; their longest such run since December 2015 (under Louis Van Gaal).
- This was just Valencia's second draw in their last 18 group games in the Champions League (W8 D8), with the previous one coming back in November 2012 against Bayern Munich (1-1).
- Manchester United have faced Valencia on more occasions without losing than any other Champions League opponent (P7 W2 D5 L0).
- Three of United's last four games against Spanish opponents in the Champions League have finished 0-0 (previously against Real Sociedad in November 2013 and Sevilla in February 2018).
United have one more home match before the international break, with Newcastle United visiting Old Trafford in the Premier League on Sunday. They resume Champions League duties against Juventus on October 23.
Valencia will play Young Boys at Mestalla on matchday three, but their more pressing concern is a home game against LaLiga champions Barcelona on Sunday.