CHARLOTTE, N.C. -- Denny Hamlin says a potential flaw in the design of the fuel cells at Joe Gibbs Racing may have contributed to Sunday's loss at Bristol Motor Speedway.
Hamlin was leading on the green-white-checkered restart, but his car stalled because not enough fuel reached the engine.
That allowed Jeff Burton to blow past the 2006 Sprint Cup rookie of the year for his first win at the half-mile track and set up a 1-2-3 finish for Richard Childress Racing. Hamlin, who got his car going after gas swashed into the engine in the corners of the track, finished sixth.
It wasn't the first time this has happened.
"Anytime we get low on fuel, especially with a banked race track like Bristol, all of our fuel drains in the cell to where we don't get any in the engine," Hamlin said Tuesday. "Once we do take off all we're using is fuel in the lines. There's a bubble in there and the car stalls."
Hamlin said team owner Joe Gibbs met with engineers all day Monday looking for answers. He said officials are also looking into why the gearbox in his car failed the previous week at Atlanta and the one in teammate Kyle Busch's car failed with him in the lead at Bristol.
"He blew the top seal out of his," Hamlin said. "Mine blew the bottom seal. As far as knowing exactly what's causing it, I don't know yet. Between steering boxes and fuel, it's aging me pretty bad."
Hamlin, who made the championship chase the past two seasons, is 15th in points after five races despite having cars capable of winning at Daytona and Bristol.
"It's just a sad situation," said Hamlin, who led 98 laps at Bristol.
Sunday was particularly disappointing for the Virginia native. He noted that Dale Earnhardt Jr., who also stayed out instead of pitting on the previous stop and was in a similar fuel situation, had no problems.
"We weren't cutting it close on fuel," Hamlin said. "We weren't even close to cutting it close. We've just got to change the design, I guess."
Hamlin said there are several ways to design a fuel cell. One is so that it always works well with low fuel; another is where under green-flag conditions a car can "suck out the gas to where there's only one drop left."
"I don't think anyone is immune to the problem," Hamlin said. "It just seems for whatever reason, design or whatever, it's not working for us. The same thing happened last year at Bristol. I was leading [late] and it just wouldn't pick up."
Hamlin also had issues at Atlanta in October, but that was attributed to water getting in the fuel of his car and many others. He finished 24th in that race, giving him five finishes of 20th or worse in the 10-race Chase for the Cup after having only four in the first 26 races.
He finished 12th in the Chase after being third in points entering the playoff. He believes the bad luck has carried over into 2008.
"It's frustrating," Hamlin said. "I've got to be cursed."
David Newton covers NASCAR for ESPN.com. He can be reached at firstname.lastname@example.org.