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 Civic.
The P0730 code indicates an incorrect gear ratio, often pointing to internal transmission problems or solenoids or fluid pressure issues. For the pressure control solenoid, a normal reading should generally fall between 14 and 25 ohms. If you're getting 5-6 ohms, that indicates a possible failure within the solenoid, which could cause your shifting issues.
Given the symptoms, ensure you also use Honda-approved transmission fluid like ATF-Z1 or DW-1, as incorrect fluid can exacerbate shifting problems. Since you've recently replaced the fluid, ensure it's at the correct level with the vehicle warmed up and on level ground.
If the solenoid checks out but you still have hard shifts or slippage, the issue could be internal transmission wear or a failing clutch pack. A transmission shop can test line pressure and diagnose further if needed.
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!
