07 with 2.4 little power in first or second. but fine in 3,4,5
 

when i hit the gas in first or second gear im only getting to 1200 rpm with sudden jumps to 4000+ 6 mechanics all dumbfounded... all other gears work fine. any ideas?

Did you try taking the vehicle to your local GM dealership? It is not clear if you took the vehicle to the dealership or simply to a mechanic. You can feel free to contact me through a private message with more information and I would be happy to assist you. It would also be helpful if you could provide your full name, address, and the VIN for the vehicle within the private message. Thank you and I look forward to hearing from you.

Tricia, Chevrolet Customer Service.

EVAP problems can restrict power.
MAF sensor problem
Transmission problem
Is the Check Engine light on?

can youn be more specific in it's actual behavior? it jumps? as in actual engine rpm or it's not smooth? surges? does it idle ok, how abour free revving? Is that ok? what about decelerating at higher RPMs in the affected gears.

gm dealers are pointless. my car has 60,000 miles and has been in 7 times all for trans issues and they still wont replace it. the cat was removed after gm said it was that and no differance so that was replaced. they also tried saying it was my clutch slipping so that was replaced no differance. throttle body swapped with buddies to see if that was it... same problem. now they are saying its a sensor down by my gas pedal. rpms jump and car runs ok then goes back to restricting power. going nuts here...