Hillenburg began motorsport competition at age eleven in the Indianapolis soap box derby. He won state quarter midget championships continuously from 1975 through 1979. He graduated through the ARCA ranks and claimed the ARCA Super Car Series Championship in 1995 with crew chief Bob Dotter, a three-time ARCA title winner in his own right. That same year Hillenburg won the Daytona ARCA 200, the series' most prestigious event, and repeated that victory in 1997.
Hillenburg also served as a test driver for the International Race of Champions and the Team Racing Auto Circuit series. He competed in the 2000 Indianapolis 500, finishing 28th. In NASCAR he made sixteen Winston Cup starts, nine Busch Series starts, and four Craftsman Truck Series appearances. His best NASCAR result was a third-place finish in the 1999 NAPA Auto Parts 300, where he drove the No. 18 MBNA Pontiac Grand Prix for Joe Gibbs Racing.
Hillenburg operates the Fast Track High Performance Driving School alongside Fast Track Racing, his competition team in the ARCA Menards Series. The organization has fielded multiple entries, running cars numbered 01, 9, 10, 11, and 12 at various points.
Fast Track briefly entered NASCAR's top series. The team fielded the No. 47 and 48 trucks in the NASCAR Camping World Truck Series from 2007 to 2010 and entered a No. 10 truck in two 2003 Craftsman Truck Series races. Their sole NASCAR Cup Series attempt came at the 2007 Daytona 500, when they entered the No. 71 Ford driven by Frank Kimmel, but the car did not make the field. Hillenburg also entered Busch Series races under his own car number 42 in 1992 and 1993, running a part-time schedule in 1994 before returning with a No. 25 entry at Dover in 1997.
On October 2, 2007, Hillenburg purchased North Carolina Speedway in Rockingham, North Carolina from Speedway Motorsports Inc. and chairman Bruton Smith for $4.4 million. The track, often called "the Rock," had not hosted a NASCAR event since 2004 before the sale. Hillenburg worked to reintroduce racing at the facility, and the ARCA RE/MAX Series returned to Rockingham in 2008 for the Carolina 500 and again in 2009. The track hosted its first NASCAR-sanctioned event since its closure when the Camping World Truck Series raced there on April 15, 2012. Rockingham remained on the Truck Series schedule in 2013 before being dropped from the 2014 calendar.
Beyond motorsport, Hillenburg has appeared in several film productions. His credits include the ESPN biographical film 3: The Dale Earnhardt Story, the Disney comedy Herbie: Fully Loaded, and the Will Ferrell comedy Talladega Nights: The Ballad of Ricky Bobby. He also served as a technical advisor and provided vehicles for the Bollywood film Ta Ra Rum Pum, which was filmed at Rockingham and at the ARCA race at the Milwaukee Mile.
Andy Hillenburg's career traces an arc from karting champion to ARCA title winner to steward of a historic American oval. His 1995 ARCA championship and back-to-back Daytona ARCA 200 victories placed him among the top drivers in that series' history, while his purchase and revival of Rockingham Speedway preserved a track that had hosted NASCAR events since the 1960s and allowed it to continue as a venue for lower-tier competition through the 2010s.