Coughlin comes from a prominent motorsport family whose JEGS brand became synonymous with performance parts across North America. His father's business provided not only sponsorship but also a foundation of technical knowledge that shaped Jeg Jr.'s understanding of the Pro Stock cars he would later master. He began competing in NHRA Sportsman categories before making the leap to professional racing, winning the Super Gas world championship in 1992 as his first national title.
Coughlin entered full-time Pro Stock competition in 1998, immediately earning NHRA Rookie of the Year honors. The following season he reached five final rounds, and in 2000 he broke through decisively — winning ten events in fourteen final-round appearances to capture his first NHRA Pro Stock Championship.
His second championship came in 2002, driving a Chevrolet, with a dominant late-season run that included victories in eight of the final twelve events. The consistency that defined his career kept him in title contention across subsequent seasons, and in 2007 he returned to the championship circle driving a Chevrolet Cobalt for Victor Cagnazzi Racing. A fourth Pro Stock title followed in 2008, during which he reached five final rounds and never fell below fourth in the season standings.
After a year away from the full schedule in 2011, Coughlin returned in 2012 driving a Dodge Avenger. On November 10, 2013, he clinched his fifth Pro Stock championship after his chief rival was eliminated in round two at Pomona, California — a title that placed him among the most successful drivers in the category's history.
He subsequently raced with Elite Motorsports, joining Erica Enders as a teammate and driving Chevrolet Camaro machinery under SCAG Power Equipment and Outlaw Light Beer sponsorship.
Coughlin holds several NHRA records that underline his versatility across the sport's many categories. He is the only driver to collect victories in four separate categories during a single season, accomplishing the feat in 1997 by winning in Pro Stock, Super Stock, Competition, and Super Gas. He is also the only professional drag racer to have won a national event from all sixteen qualifying positions, a mark that speaks to his ability to perform regardless of starting spot. He is one of only two drivers to have won at a national event in seven different classes, including Pro Stock, Competition, Super Stock, Super Comp, Super Gas, and Top Dragster.
In 2001, Coughlin set a national elapsed-time record at Reading, Pennsylvania with a 6.750-second pass, and continued to improve on that benchmark over subsequent seasons. By the time he reached the peak of his career, he held a combined total of 46 wins across the professional and sportsman series, along with 12 NHRA Lucas Oil Sportsman Series victories.
Coughlin's five Pro Stock championships and remarkable cross-category record-setting place him in the upper tier of NHRA competition history. His ability to win from any qualifying spot, compete in multiple classes at the highest level, and sustain championship-caliber performance across more than fifteen years of full-time competition set a standard that few Pro Stock drivers have approached. He remained a respected figure in the NHRA paddock both as a competitor and as a representative of one of drag racing's most recognizable family brands.