Key TakeawaysShares of AAP plunged 16% during premarket hours to $46.92 following disappointing Q2 comparable store sales resultsAdjusted earnings per share of $1.03 surpassed analyst expectations of $0.81, while net revenue of $2B fell short of the $2.04B consensusComparable store sales declined 0.5% versus Wall Street’s anticipated 1.4% increaseCEO Shane O’Kelly cited constrained consumer budgets impacting the do-it-yourself segment, particularly during the quarter’s final monthAnnual adjusted earnings outlook increased to a range of $2.60-$3.30 from the previous $2.40-$3.10 projectionShares of Advance Auto Parts (AAP) tumbled 16% to $46.92 during Thursday’s premarket session following the automotive aftermarket retailer’s second-quarter results that showed a divergence between profitability and top-line performance.Advance Auto Parts, Inc., AAPPrior to Thursday’s trading, the stock had climbed 43% since the beginning of the year. That impressive gain evaporated quickly.The company posted adjusted earnings of $1.03 per share for the second quarter, representing significant growth from $0.69 in the prior-year period and exceeding analyst consensus of $0.81. However, net revenue reached $2 billion, falling slightly below the Street’s $2.04 billion projection and essentially unchanged from last year’s $2.01 billion.$AAP Advance Auto’s $1.03 beat came with a $0.31 asterisk.The breakdown •Adj. EPS: $1.03 vs $0.81 est $0.31 was tariff refunds.•Net sales: $2.00B vs $2.03B est; comps -0.5%.•Adj. op margin: 5.6% vs 3.0% LY.•FY26 adj. EPS: raised to $2.60-$3.30 (on interest… pic.twitter.com/Q7dY2urDaC— Invest Alpha Pro (@InvestAlphaPro) August 20, 2026It’s important to note that tariff-related refunds boosted the adjusted earnings figure by approximately $0.31 per share, providing meaningful context to the bottom-line performance.Comparable store sales decreased 0.5% during the quarter. Analysts had projected a 1.4% gain. This shortfall triggered the sharpest investor reaction.Do-It-Yourself Segment Faces HeadwindsChief Executive Shane O’Kelly attributed the underperformance to challenges in the company’s DIY business segment.“Total enterprise sales performance was impacted by the DIY channel as tighter household budgets constrained spending more than we anticipated, especially during the last four weeks of the quarter,” he said.O’Kelly characterized the broader demand landscape as “volatile.”While the professional business segment delivered low-single-digit percentage gains, providing some balance, this growth proved insufficient to elevate overall comparable sales performance.The market reaction extended across the automotive aftermarket sector. AAP‘s struggles dragged down AutoZone (AZO) by 2.2% and O’Reilly Automotive (ORLY) by 2%.Revenue Outlook Unchanged, Profit Forecast RisesRegarding forward-looking projections, AAP maintained its full-year net revenue guidance of $8.485 billion to $8.575 billion, anticipating comparable store sales growth of 1% to 2%.The company elevated its annual adjusted earnings per share guidance to a range of $2.60-$3.30, up from the prior $2.40-$3.10 band. Leadership cited increased pretax interest income as the driver behind the improved profitability outlook.Wall Street analysts have begun recalibrating their price objectives, factoring in execution challenges and the temporal disconnect between capital deployment and financial returns. Market sentiment has evolved from post-earnings optimism to a more cautious perspective regarding near-term quarterly trends.The company operates with substantial debt levels and negative free cash flow generation, constraining its operational flexibility should revenue performance continue to lag expectations.Advance Auto Parts currently maintains a market capitalization of roughly $3.43 billion, with typical daily share volume of approximately 1.87 million.The post Advance Auto Parts (AAP) Shares Plunge 16% on Weak DIY Sales and Missed Revenue Targets appeared first on Blockonomi.