Hello! Just got myself a 1996 sti. The car is in great nick with low k's for age but ever since i did a oil and filter change on it about three days ago it has not liked being started cold. This is not a regular thing, only happens one out of three cold starts but the thing is if i leave in outside over night and i come to start it in the morning it will idle very low as if it is restricted of something but as soon as i give it a bit of gas its sweet! Just seems to me it shouldnt be doing that! When i start it warm its fine! Not to sure what it could be. Have been told its just cold but its not THAT cold overnight, probly about 10 degres celcius so its not freezing! Seems to me like it could be a auto choke problem? Any help would be great