Check the TPS(throttle position sensor), it serves the same purpose as the Accelerator Pump on a carb.
On a carb when you pressed down on the gas pedal the accelerator pump would squirt extra fuel into the engine to speed up RPMs until air flow started sucking enough fuel out of the main jets.
On fuel injected engines there is a MAP or MAF sensor that is used to read the air coming into the intake, when you press down on the gas pedal there would be a lag before air flow increase was seen by the sensor and then the computer, so TPS sensor was added, if gives computer instant data on driver input in gas pedal position.
It can be checked with a volt Meter.
TPS has 3 wires, top, center and lower
Set volt meter for DC volts, 20vDC is a common Meter setting.
Remove plastic cover over throttle linkage, if it's still there, you will need to manually move the throttle during test.
get a sewing pin, straight pin, to pierce the wires for testing voltage
Turn on key
Insert pin into top wire, measure voltage, should be 4.8v to 5volts
Move pin to center wire, it should have .69-.99volts, below 1 volt
With meter on center wire start to open throttle, voltage should go up steadily, no jumping around, at Full throttle voltage should be above 4.5volts.
Close throttle and watch voltage.
If there are "dead" spots or places where voltage jumps replace TPS.
Lower wire is a Ground