Kaname Yokoo stayed in second place after matching Woods with a 67 in the second round.
Christian Pena fired the lowest round of the day on Friday with a 7-under- par 63. He is alone in third place at 4-under-par 136.
Thursday's opening round featured heavy downpours and that rain helped course conditions on Friday. The greens were soft and receptive and every player in the top-17 shot par or better in round two.
Woods collected his first birdie at the fourth hole, then birdied No. 8 for the second time in as many rounds. He added another at nine, then birdied the par-4 13th, but ran into trouble at No. 16.
Woods landed in a greenside bunker at the par-4 hole and blasted out to 12 feet. He two-putted for a bogey, his first in 56 holes at this tournament, but parred out for the lead at the halfway point.
If Woods can hang on the rest of the weekend, he will earn his first stroke-play victory of the season. He won the WGC-Accenture Match Play Championship, but dropped his spot atop the World Rankings when Vijay Singh defeated him at the Deutsche Bank Championship on Labor Day weekend.
K.J. Choi (66) and Ryoken Kawagishi (67) share fourth place at 2-under-par 138, while Hideto Tanihara (70), Joe Ozaki (65) and Daniel Chopra (68), who earned his 2005 PGA Tour card through the Nationwide Tour in 2004, are tied for sixth at minus-1.
Robert Allenby shot a 1-under 69 and is part of a group tied for ninth at even-par 140.
Defending champion Thomas Bjorn carded a 69 on Friday and is part of a logjam in 32nd place at plus-4.
Stewart Cink, ranked 10th in the world, posted a 3-over 73 and is tied for 57th at 8-over-par 148. Reigning British Open champion Todd Hamilton shot a 6-over 76 and made the cut on the number at 9-over-par 149.