Engine running rough at idle and hesitating on acceleration in 2005 dodge ram?

[Duster]

I have a 2005 Dodge Ram 2500 with the 5.7L HEMI engine and 78,000 miles on it. Last week it really started idling rough when i would first start it up as well as just about die when i would slightly depress the gas from an idle. It runs fine when you mash down on the pedal and even cruse down the road at a good speed. It only seems to do it when it is either idling or when i slightly depress the pedal especially when its in gear starting out from a stop. I thought it might be water in the gas which has happened before so i added some water remover and some fresh gas. It still did it. So i thought it might be dirty injectors so i added some gum-out with some fresh gas. it still did it. I really don't know whats causing it but its really starting to get annoying. i thought it might be bad oxygen sensors but those don't even control the fuel air mix when you first start the engine so now im thinking it might have something to do with the electronic throttle. I am going to take it to the dealer friday and have them run diagnostics but if anyone out there can just point me in the right direction of what might be wrong i will know friday when the mechanics tell me there not just trying to screw me over. Thank you so much