have 2007 dodge ram 1500 hemi and when i step on the accelerator then release then i step back again the engine seems powerless until i step down more on the accelerator

Is this at a stand still with it in park or neutral? Or is it at highway speeds when you step on the gas?

it is at highway speed

Ok. These tend to feel powerless when they have dropped back to running on four cylinders and you then give it the gas. All cylinders have to kick back in then it will drop out of overdrive and that's when you feel the power kick back in. Took me a while to get use to mine doing this. But if you know what that feels like and this feels different to you then I would ask how old are your spark plugs? Mine regained a good bit of power when I replaced all sixteen of mine.

first thank you for the useful information . the first thing came to my mind when this happen was the spark plugs . but it turns out that the problem is not the spark plugs. about a year ago when i bought the car ,the check engine light was on because the air temperature sensor was missing. four days ago i found this sensor and by disconnecting the battery the light was off but kept on and off .today i took the car to the mechanic and told me the was the evaporator gas and you know what the worst part,the mechanic deleted the code to keep the light off