If you can, how to you set idle down for cold start

What is your question?

I would like to know if and how to set the cols start idle down. Mine is between 2000 and 2200 rpms. I understand some say it is normal as long as it doesn't remain that high for long. But, my engine is making a noise at the cold start idle that high and I want to preserve the engine, so to speak, so would like for it not to be that high. Not sure if it is the top or bottom half of engine. Could be the lifters or rods, don't know, but feel that that high of a idle first time starting is to high and not healthy for this 126K engine. Please answer this question as to setting idle.