[LH Lead-Foot]

When you key on with an engine using DBW, the throttle valve can stick in the bore of the housing. The system is designed to kick open the throttle blade about 5mm, then close. If stuck due to temperature change, freezing humidity causing ice or frost, it will knock it loose. If not, it will set a code. I have seen freezing on the old school Ford VV carb and on Volvo down draft, CIS fuel system.
Remember, there are no bad questions. This is a friendly place of learning. Someone always knows more than me, but I can share with you information to save money and fix your vehicle right, unlike my boys who did not care, perhaps my 40+ years of experience can help. Even though I was contract labor for ACDelco for 7 years, a handful of us where called "Legacy Instructors". I did not know what that meant, but a guy told me; "You an ASE Master right? yes. You have ASE L1 certification right? yes. You have worked on fuel injection using a 3 or 4 gas analyzer right? yes. Did you go to technical trade school? no....You're a legacy instructor due to your experience, so pass it on to other so they can repeat the customers concern, diagnose the root cause and fix the problem right the first time. PM me if you feel better about questions and provide photos if you can. Testing, like voltage drop is quick, correct, and will never lye to you...and will always allow you to find the problem in a circuit.
Always ask yourself... is this a symptom or the ROOT cause?
3 Things to remember when it comes to electrical;
#1 A test light will how the presents or absence of electrical potential
#2 A DMM will perform voltage drops and current measurements
#3 A lab scope will show you to "See" the electrical activity in a circuit. A trained eye & experience will tell you if it is right or wrong.