2005 Hyundai Santa Fe P0455, P0510, and P2125 Diagnostic Issues: Throttle Body Warranty Concerns

I own a 2005 Hyundai Santa Fe with a 3.5L engine and currently have 62,000 miles. On August 12, I replaced the acceleration positioning sensor at a cost of $400. In January 2013, during a dealership service, it was determined that my throttle body sensor was faulty. However, instead of replacing just the sensor, they installed a complete new throttle body assembly—this included the throttle gasket and crankshaft position sensor—and also replaced the fuel cap for $117.20. In February 2 as the engine light came on. The dealership initially told me that the engine light could come on intermittently without any performance issues, so I didn’t take further action. A few months later, the engine light returned again. I let it go for several months with no noticeable driving problems. Eventually, I took the vehicle to a service station mechanic who performed a computer diagnostic and found three trouble codes: P0455 (Evaporative Emission Control System Gross Leak Detected), P0510 (Closed Throttle Position Switch Malfunction), and P2125 (Throttle/Pedal Position Sensor 'E' Circuit). Regarding P0455: I’ve checked the gas cap and confirmed it is securely fastened and properly seated. For P0510 and P2125, these codes strongly suggest a problem with the throttle body assembly. Since this component was recently replaced under warranty, I believe it should be re-inspected by the dealership to verify proper installation and functionality. As a 66-year-old woman who has limited trust in dealership services or independent mechanics, I’m concerned about potential hidden costs. I’d like to know: Is it likely that these codes are directly related to the original throttle body replacement? If so, will the issue be covered under warranty? If not, what additional parts or labor might be required for repair? Any advice on how to handle this situation professionally and cost-effectively when returning to the dealership would be greatly appreciated. Thanks, Carol.