2008 Jeep Grand Cherokee 5.7L Hemi: P013C and P0330 Error Codes Explained - Warranty Concerns After Head Repair?

I currently have two diagnostic error codes on my 2008 Jeep Grand Cherokee with the 5.7L Hemi engine: P013C and P0330. After reviewing several forum threads, I've noticed that many owners experience the P013C code repeatedly — often after multiple troubleshooting attempts — and it tends to resolve temporarily before returning. While this has happened to me 2-3 times over the past few years, I'm not overly concerned about P013C at this point. The P0330 code is more concerning: it indicates 'Circuit Knock Sensor (#2) signal above or below minimum acceptable threshold voltage at particular engine speeds.' This suggests a potential issue with the knock sensor circuit or its connection, which could affect engine performance and potentially lead to damage if unresolved. My real question is whether this P0330 code might be related to recent repairs. A fun backstory: in July 2014, my water pump failed, leading me to have my Jeep at a repair shop for an extended period. During the water pump replacement, the engine cover was removed and inspection revealed that one cylinder head was misfiring. As a result, two heads were repaired. I received the vehicle back about two months later. Now, nearly three months after that work, I've started seeing the P0330 code again. Could this be related to the previous head repair? The service came with a 2-year nationwide warranty — does that cover potential sensor or engine-related issues stemming from those repairs?