2008 Chevrolet Aveo sputters in gear

6 months ago car I started the car and waited for it to idle down started to go forward car was sluggish and barely moved, I thought maybe it’s cold so i continued and took it around the block no acceleration. Parked the Car had mechanic look at it . change spark plugs wires and ignition core. Car still missing. change egr valve and actuator. still missing checked timing belt and catalytic converter all good. what is wrong with this car ? It starts up like there is nothing wrong but when you put in gear to move it starts sputtering. We also checked the peddle sensor

is there a check engine light on? If so, have you had the codes checked? If so, what are they?