The engine P1138 Code comes from the powertrain problem and this problem is not tough to solve. The powertrain problem is important to solve. Although, this problem is small and it can be fixed easily, do not ignore this problem. By the wrong meaning of the code, you cannot solve the car engine problem but you can use automobile dictionary meaning and it is p for Powertrain Code Problem is related engine, transmission and emissions systems. 1 for MFG – Manufacturer Specific. 1 for Transmission. 3 for Cruise Control Servo Indicates Low and 8 for PCM Stack Overrun. After testing the car, you can drive it.