You need to solve the car engine problem and in this case, you need to fix the car engine by an expert. The car engine P2728 Code helps in this problem. The powertrain of the car is easy to solve. However, you must know the meaning of the code if you want to solve the car engine by yourself or by any other person like a technician. The general meaning of the code is p for Powertrain Code Problem is related engine, transmission and emissions systems. 2 for MFG – Manufacturer Specific. 7 for Auxiliary Emission Controls. 2 for Air Conditioning (A/C) Clutch Feedback Circuit High Voltage and 8 for PCM Stack Overrun.