The lack of response to the accelerator pedal has quite a few potential causes that would have to be sorted out in a diagnostic including, just as a few examples, plugged fuel injectors, faulty oxygen
sensors, fuel pump and / or filter, vacuum leaks including that caused by a faulty EGR system, ignition system
malfunctions, bad valve timing if the timing belt or chain is worn or skipped, blocked exhaust (e.g., catalytic converter fails or becomes clogged), a faulty airflow
sensor or
throttle position sensor, and so forth.