I had the same problem and it turned out to be the fuel purge censor
Hyundai accent idle speed
it seems there a small screw back of the intake but the idle is control by the ecu.
When a car, such as a Hyundai accent, has and broken idle control valve the engine may or may not start. Idling is controlled by this part and the car a malfunctioning unit can cause the car to act erratically, such as starting at random times and stalling.
It is just next to the TPS (Throttle Position Sensor) on the intake manifold.
Could be IAC idle air control, or maybe a vacuum leak check hose first
the engine to stall and surge at idle
auto or stick shift
i dunno shut ur fat gob plz bye bye bye bye your a doofus and a baby so be quiet plz haha haha lmao ( ^ _ ^ )
Probaby a sensor.
The Idle Speed misadjustment, Timeing misadjustment, or bad throttle position sensor. Search one of the 4WD forums like IH8MUD.com or Pirate4x4 for idle surge. check the coolant level.
maybe the clutch
Because the engine is running. Shut it off or give it gas and it will not idle.