The first birdie came first on hole 13 and was followed at a fast pace by three more.
Unfortunately, the round also offered three bogeys and Norén went around one stroke under par and has a total of -10.
The competition in Jersey City is the first in this year's Fedex Cup, the PGA Tour finals where a winner is crowned in three weeks.
For Norén to be one of the 70 who will continue to play in the BMW Championships in Maryland next week - and continue to compete for the prize money of more than SEK 500 million - he should probably end up in the top 19 this weekend.
Australian Cameron Smith, who made a full eleven birdies on Saturday, shares the lead with Spanish world setter Jon Rahm.
They both have -16.
However, none of the players will show up on Sunday.
The storm Henri is threatening northern New Jersey and the final round has been postponed until Monday.
CLIP: Alex Norén fourth in Detroit (July 5)
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Alex Norén happy after the PGA competition in Detroit.
Photo: TT