Empowered by increased spending on auto repairs, due to stimulus packages and new vehicle inventory shortages, automotive replacement part retailers have been red-hot. This strength was on display again this morning when Advance Auto Parts (AAP) reported upside Q1 results, featuring strong comparable-store sales growth of 24.7% versus the 22.5% consensus estimate. The company also raised its FY21 guidance for the second time since issuing Q4 results in mid-February.AAP’s outstanding results hardly come as a surprise, though. Last week, peer AutoZone (AZO) blew out expectations as same-store sales soared by nearly 29%. That report came on the heels of a beat-and-raise performance from O’Reilly Auto (ORLY) on April 28.Consequently, AAP faced high expectations heading into its print, as illustrated by the stock’s ~23% year-to-date gain. Given the stock’s sharp run higher, we believe that the impressive Q1 report was already priced into shares.Sky-high expectations aside, there was plenty to cheer about regarding AAP’s results. Sales jumped by 23% yr/yr to $3.3 bln, representing a quarterly record for the company, and were bolstered by healthy demand from both DIY (do-it-yourself) and professional clients. It’s worth pointing out, though, that total sales and comparable store sales growth were aided by favorable yr/yr comparisons as AAP laps the most severe effects from the pandemic. In the year-earlier quarter, comparable store sales were down 9.3% due to stay-at-home orders that significantly reduced car counts and retail traffic.