HARTFORD, Conn. -- Shares of Advance Auto Parts Inc. fell in premarket trading Thursday as two analysts described its do-it-yourself business as soft and lackluster despite an increase in second-quarter profit and revenue.

Sales at stores open at least a year, a key measure for retailers, rose 4.8 percent, the Roanoke, Va. company said Wednesday. That included an increase of 14.8 percent for commercial sales and 0.7 percent for the do-it-yourself business.

"We suspect investors will be disappointed by the soft DIY comp," RBC Capital Markets analyst Scot Ciccarelli said in a note to investors. "In addition to more difficult comparisons from last year's stimulus activity, we believe that the inventory changes - towards more hard parts and away from accessories - may have adversely impacted DIY growth," he said in a note to investors.

Morgan Joseph analyst Jeffrey Blaeser said the company's strong earnings growth "could be overshadowed by lackluster retail comp sales."

Advance Auto Parts ( AAP - news - people ) said Wednesday it earned $80.3 million, or 83 cents per share, during the quarter, up from $75.4 million, or 78 cents per share, during the year-ago period. Excluding a charge of 6 cents per share, the company would have earned 89 cents per share.

Revenue rose 7 percent to $1.32 billion from $1.24 billion a year earlier. Analysts surveyed by Thomson Reuters were expecting a profit of 83 cents per share on revenue of $1.31 billion.