standar elantra wagon losing power...not accelerating with foot on pedal

Possibly your throttle position sensor has failed AC Delco, Airtex, Borg Warner,Delphi and Standard ignition all carry them, So it must be a common part that fails, about $90 to $100 and about 1/3 hour to replace

Has your Check Engine Light come on. Loss of power could be many things. Could be a loss of fuel delivery due to failing pump, restricted filter ect.... Could be a failing air flow meter, the airflow meter tells your computer how much air is being drawn into the engine. If a Check Engine Light is on that will lead to area needs to be diagnosed to find the fault even if the light is not on a scan tool can be used to read data coming from key engine sensors.