Saturn Repair Problems? Ask a Mechanic for Answers ASAP
Hello, my name is Bobby. Thank you for the question. There are a few common cause of this. The most common is a dirty throttle body. If the throttle is dirty then it will have trouble holding an idle until the engine warms up. It can also be the coolant temperature sensor. If it is reading a colder or warmer than normal temperature in these cold conditions then it will run like this. I would have the throttle body cleaned first as that is the easiest place to start. Please let me know if you need more help.
You really need to start with cleaning the throttle body. When it is dirty it will cause the engine to starve for air. This will continue until the engine computer decides to adjust the idle control valve to change the idle.
Most of the time it is due to the expansion and contraction of these metal parts. It affects things like the throttle body since the bore is aluminum and the plate inside of it is not so they expand at different rates.