The automobile dictionary meaning of the car engine code can be used for solving the car engine. The car engine P2686 Code’s right meaning should be fixed first. If the real meaning of the code is not found, you may use general meaning for solving the car engine. The 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. 8 for Exhaust Gas Recirculation System Valve 1 and 6 for Cruise Control System – Vehicle Accel Too High.