The parts or components from the car engine may not be necessary to replace. The engine gives you reference about the engine problem and when the car engine tested then the only engine code P1574 DTC is found. The car service manual should be read to collect for more information about the car engine problem and possible causes of the fault It may necessary more testing to know the real cause of the car engine. The engine code is important but it is not enough. It is better if you leave the car engine to automobile repair center to fix the car engine issue.