Hesitation / small "kick" during idle

Hi Guys,

I have a 2006 Mazda 3 GT with approx 120k KM's on it that has developed a bit of a problem. When I do a cold start the car runs great until it warms up, however once it warms up it has some pretty sever hesitation. The hesitation happens through the entire gear range but is less noticeable in first gear and most apparent in 4th and 5th. While idling, the motor kicks ever so slightly, enough that you can feel it but when looking at the tach, it doesn't move at all and is idling perfectly at 700 rpm. I have no engine light on either. Help would be greatly appreciated!

-Josh

Update.

Last night I pulled the plug on the battery to reset the ECU, this made things worse. The battery light is now on but will flash off when the car bucks (which is now MUCH worse then it was prior to resetting the ECU). The car will also not rev past ~5k rpm. Also the first time I go to start the car it stalls but the second time it will start no problem.

Anyone experience this before?

-Josh