2006 SAAB 9-3 repair Question Car runs weird when parked out

My car, after a warm restart runs like crap. At the lower speeds (when trying to bring the rpms up while barely feathing the pedal) the car bucks, shrugs, and has serious power loss. Now if I mash the pedal when those symptoms are happening, the bucking stops, but the car gains speeds as slow as a turtle.

I've spoken to the dealer about it and they said "they couldn't replicate it" When those symptoms happened, I had Knock retard up to 7.

No CEL's have been thrown and this is making it difficult to diagnose. I will be speaking to my dealer about this again today and any help would be appreciated.

Please note that after the car has reached optimal tempratures, it runs beautifully, and that this problem only started when the temperature outside have been cold.

EDIT: You should also know that my car has an after market tune. Those symptoms are present on both tuned and stock, but are way more pronounced when tuned.

I use 94 octane as well.

Thanks a lot.