weird miss....any ideas???

[cody161]

back over the summer i put a holley 58mm throttle body on my car and ported the intake. as the weather began to gradually get colder there was a slght miss from 2000 to 3000rpm. now that the weather is really cold it has a terrible miss when u first crank the car up and gradually gets better as the car warms up, but it is still pretty bad from 2000 to 3000 rpm steady throttle. yesterday was a 65 degree day and the car ran decent, alot better than it does on 20-40 degree days. i put new plugs in 2000 miles ago and the car has been on a scanner and nothing looked out of the ordinary and my tuner says the throttle body wouldnt throw it off that much. and we dont think it is the O2 sensors cassue the car is on open loop when it first cranks and it has the really bad miss then. any ideas, im tired of having this miss!!!