08 cobalt help help

[mrcoffee]

hi all im a brand new member cause just baught a 08 cobalt with 16,000 miles
lady wrked 3 days a week and didnt drive much so good deal..
anyway i had it for a week and noticed when i drive anywhere between say 28 or 30 to up to 50ish i get this surging like the tach goes up from say 300 to 500 rpm and it kinda does a little surging kinda annoying..but once im cruising down the road say 55 to 70 shes purring nicely no probs
.. well come to find out back in apr at 14,000 miles the previous owner took it in and the torque converter was replaced cause i guess what ever was wrong then they deamed it to be the torque converter prob.. anyway i only found this out after reading my vehicle readout the dealer gave me on the car that showed all the work that was done on the car which included the recall of the power stearing motor thingy..so when i took it in tuesday they did more research etc etc and figured after talking to some higher ups i think that they are scheduling me for this week on tuesday and taking tranny all apart they say and see whats going on...
so im asking has anyone dealt with this problem at all... they said it was prob torque converter not working right when we did the test drive until they then since found out that it was already changed in apr..
still under warrantee they are taking care of it all but wondering if i should recommend to them cant they just do me a new tranny all together cause if it wasnt the torque converter then what could it be.. ok so if anyone has any info to add to this for me id appreciate thanks much i will be hitting this forum lots i guess... hi to all. oh ya its the 2.2 engine automatic