The automobile dictionary meaning of the car engine code is important and you can use this meaning for solving the car engine. You can use the general meaning of the code for study about the code and engine problem. The car engine P2656 Code is helpful for solving the car engine and general/automobile dictionary meaning of the code is p for Powertrain Code Problem is related engine, transmission and emissions systems. 2 for MFG – Manufacturer Specific. 6 for Vehicle Speed Control And Idle Control System. 5 for TP Sensor Learn Not Complete and 6 for Cruise Control System – Vehicle Accel Too High.