When I got my '03 Sorento back from having the short block replaced after the crank bolt broke it developed an acceleration problem within a few days. I found that at times it would all the sudden get sluggish at 50MPH and I would not be able to go any faster then that. Took it in and they told me it was the transmission speed sensor which they replaced. A day after getting it back the same problem occured, this time though it was sluggish at 35MPH and I could to go any faster than that. Took it back to Kia and they said it was the fuel pump which they replaced. The car ran fine for a week until it happened again. This time I decided to hold off taking it back in and filled the tank with high test. My observation is that this sluggishness and inability to accelerate starts to happen when my fuel level is at about half a tank. If I fill it I will not have this problem until I get down to half a tank of gas. Any suggestions as to what could be causing this problem? Thanks
go to a different shop. get an oil change and look underneath the car while it is up on the lift. see if the gas tank has been punched in from the bottom.
then go back to original shop and kick their butts.
Thanks for the feed-back. I’ll check it out.