There are a whole lot of things that could be awry, including things like faulty spark plugs, faulty spark plug wires, faulty ignition module and faulty engine control computer, that DO NT set a code in OBDII. (mechanics.stackexchange.com)
If you make the driver's request for more torque (one way to interpret foot pressure on the gas pedal) just another input into the master engine control computer, its a lot easier to manage spark timing, transmission shifting, throttle plate opening, fuel injection rate, intake and exhaust valve cam phase angle, and (for hybrid electric cars) flow of energy into and out of the battery pack, in the smoothest and most economical manner. (autoline.tv)
The port fuel injection system is controlled electronically by a Fast XFI electronic engine control computer. (bestride.com)