I have a 99 ram 2500 starts good and stays running when I step on gas petal on 1999 Dodge Ram 2500

It feels stiff and I have very little acceleration I've changed cap rotor wires and cleaned throt.body and no change what can I do to correct this problem please

Asked by for the 1999 Dodge Ram 2500
1 answer
WHAT ARE THE ENG CODES IF ANY?