Alright when I give my car heavy gas in a low rpm's it begins a vibrating shake and starts to stutter like its not getting enough gas. It feels like my car has like no power.
I just finished putting new spark plugs in because they were due and i thought maybe that could have been part of the problem but it didnt help. From what I have read the shaking could be from the transmission mount but could that make it stutter and have barely any power??

 

check to see if you got all the plug wires on they dont always click on easily especially on the opti. also check for burnt wires

 

is the SES light on ? sounds like your opti could be going out, or your cat could be clogged