Here is a picture of the bottom of the throttle body. What is the short little tube for? Is it supposed to be hooked up to vacuum? It was not hooked up to anything, and I don’t see an errant vacuum line anywhere.

For the curious, I removed the throttle body to replace the part load breather tube. Major vacuum leak. The tube came out in pieces. Anyway, if someone can help identify the function of this little hose, I would appreciate it.

 

I managed to catch a pic of that area on mine and it looks like the tube just sits open on mine as well (red arrow)with a fair bit of oil residue on it... Maybe a condensation drain?

I did notice that the small plastic vacuum line that goes into the side of the TB was very loose on mine (green arrow), which may be my possible small leak/occasional whistling noise that I was getting from vaguely that area, that I haven't been able to trace down. The things you find on unrelated repairs on these cars...

 

Thank you! I suspect that’s exactly what it is.

I can help a little with the loose vacuum line you mentioned. That line goes to the brake booster, and it fits loosely by nature. I don’t remember what they call that type of fitting, but you push the tube in and can’t pull it out unless you push in on the surrounding black ring, just ahead of your green arrow. There’s an O ring in there that keeps it from leaking even though it seems looose. To be sure, you can spray some carb cleaner at it with the car running. If the engine revs, it’s leaking vacuum. If not, it’s good to go.

 

It did have the feeling of one of those quick-connect style lines, didn't want to mess with it too much in the dark. Got about 1/4 inch of easy movement in and out. I'll be sure to test it with the car running later in the week when I've got a chance.

 

In case it's too loose and thus lets air in it would show in fuel trims (LTFTs), especially at idle.