2013 Hyundai Accent P2414 and P2191 Fault - Abnormal Shifting and Engine Bogging
I own a 2013 Hyundai Accent with an automatic transmission. After replacing the front oxygen sensor (Gamma) due to persistent fault codes P2414 and P2191, I'm experiencing significant shifting issues. The vehicle abruptly upshifts when accelerating gently at around 30 mph, and when decelerating from 35 mph, it sounds like a manual transmission. There's also noticeable engine bogging during acceleration. I took the car back to the dealer, who updated the Transmission Control Module (TCM) for ECO mode and reset adaptive values, and also performed an ECU update for improved DTC logic. According to their documentation, the shifting should now be normal—however, in practice, the vehicle still exhibits abnormal behavior. What other potential causes could be responsible for this issue? Any insights or troubleshooting steps would be greatly appreciated.
It's recommended to revisit the dealer with detailed driving logs and shift pattern recordings to verify if the TCM update resolved the issue. Also, consider having a professional diagnostic tool check for any remaining stored or live fault codes related to P2414 and P2191, as these could indicate deeper transmission or sensor problems.