A score of 70 on Friday saw the Northern Irishman make his first cut of the season, scraping into the weekend at the Houston Open by one shot.
McIlroy, who entered the Texas Open 30 minutes before the deadline, has postponed a scheduled trip to Haiti in his role as a Unicef ambassador.
American Steve Wheatcroft shot 67 to lead at 10 under par in Houston.
England's Brian Davis (-7) and Lee Westwood (-4) are both well placed.
After an opening 73, double major winner McIlroy, who has only played 10 competitive rounds in a difficult start to 2013, was again far from fluent as he registered three birdies in a two-under par second round at Redstone.
"I needed to go out there and shoot a decent score to make sure I was in for the weekend," said McIlroy, for whom victory would see him reclaim the world number one spot from Tiger Woods.
"I played the last few holes really well when I needed to," the 23-year-old told BBC Sport. "It was a little better. It was an improvement on yesterday, which is the main thing.
"It's a weekend where I can have a couple more rounds and try and get confidence. It's more a mental thing than a mechanical thing at his point."
After his disappointing opening round, he was in danger of suffering a humiliating early exit.
Starting his round on the back nine, McIlroy scored consecutive birdies at the 15th and 16th, before dropping a shot at the second.
But he steadied himself, picking up a shot on the par-five eighth to narrowly make the cut.
McIlroy had been due to go to Haiti between the tournaments, but he has postponed that until another date.
Wheatcroft, whose consecutive 67s have given him the halfway lead in Houston, was consistent throughout Friday.
The 35-year-old American, who made only seven out of 22 cuts last year on the PGA Tour, racked up five birdies in a blemish-free second round.
On his prospects for victory, Wheatcroft said: "Who knows? I could shoot 61 tomorrow; I could shoot 71 - I really don't know.
"I'm not going to sit around here and think about it too much."
Overnight leader DA Points had a relatively quiet day, carding a 71 to go into the weekend just one shot behind compatriot Wheatcroft.
Round of the day went to yet another home player, Stewart Cink, whose 66 was enough to take him into a share of third place, three off the lead.
Westwood maintained an interest in the tournament, carding a level-par 72 for four under overall, while three-time Masters winner Phil Mickelson joined McIlroy in scraping into the final two rounds by the narrowest of margins.