Just had my cadillac cts 2011 service do to a P0301 now engine light on again?

Hi, my name is Devin. I am an auto repair expert with the Car Genius team here at RepairPal. I'm sorry to hear you're having trouble with your CTS. The P0301 code indicates a misfire in cylinder 1, and since the check engine light has returned, there may be an underlying issue that wasn't fully resolved. Common causes for recurring P0301 codes can include problems with the fuel injector, ignition coil, or spark plug in cylinder 1. It might also be worth checking for vacuum leaks or fuel delivery issues, which can lead to intermittent misfires. Returning to your mechanic for a thorough inspection of these components should help pinpoint the exact cause. If you need more advice, have any other questions about your vehicle, or would like to get connected to a RepairPal Certified shop near you, we have you covered. Give us a call at 877-913-1554, and we will happily help you out!