s4 na stutters when cold

[IH8DSM]

Just like the title says I got a na s4 all stock that's has a random stutter issue. It really only does it when the weathers cold you'll go to hit the gas and nothing rpms don't even go up pump the gas a few times and it will start to drive normal again. does it both at idle as well as when driving when I left off the gas for a second then try to get back on it.

It idles high (1500rpms) and adjusting the top screw doesn't do anything so im swapping it with a stripped down throttle body and a different tps and hoping this will fix my issue. Just curious if there's anything else I should check or change if the new throttle body and tps doesnt fix my problem.

Its got a new fuel filter on it, fresh plugs and wires, ran chemtool throguht it twice now. The motor starts when its hot or cold no problems and was supposedly rebuilt about 30,000 miles ago.