The meaning of the engine C1726 Code is necessary to know and if the real meaning of the engine is not found, you cannot solve the car engine problem. The car engine code C1726 OBD2 reports a sensor fault, extra of the sensor is doubtful to solve the original problem. The burden is the most probable to be reasoned by the method that the sensor is monitoring, but might even be produced by the cabling to the sensor itself. Once the car engine is ok, you must take the car for a test drive. If you find any problem, take back the car to service center.