Erratic idle. What's in this photo?
 

https://cimg7.ibsrv.net/gimg/www.myg...4df2ecc78f.jpg
My 2008 G37s AT almost stalls sometimes at stops. I've heard that a bullydog programmer will solve the idle issue but i can't afford it just yet i found this piece loose coming off the drivers side air intake tube. Any idea what it is? Important to get it sealed up? I pulled it loose with the car running and it didn't seem to affect how it idled.

May be a vacuum leak. I've always checked by carefully spraying starting fluid on vacuum hoses/ connections. If the idle revs up or changes any, I've found my leak. Just a thought.

Edit: Also, apologies, but I can't tell whats in the pic. Just thought this may help find a vac leak.

If I'm looking at this right (Drivers intake tube, right next to throttle body?) I was told that piece was a baffle in the intake system to reduce noise or something like that. It doesn't really go anywhere, just has some canister on that.

On a 2008, with unknown mileage, have the throttle bodies ever been cleaned?

The baffles just pop into their respective sockets.

You have a vacuum leak somewhere use a smoke machine to find it

Hi - Your first step should be to check if there any codes present to give you direction. If you have a P0506 or P0507 that would indicate idle is lower or higher than normal. As mentioned in previous posts possible vacuum leaks which can include air leaks through the air ducts (air not seen by the MAF) can lead to idle issues. Other problems like engine misfires, timing issues, dirty throttle bodies (mentioned as well) etc... can lead to poor idle. Has there been any recent work done, when did the problem start, does the idle problem occur all the time or only when multiple accessories are running? All these questions may need to be considered. Start with codes and move from there - Good luck!

Jumping back to the vacuum leak for a sec, you ever had your engine cover off? Check the centre screw, I read that these screws if pushed too far in can crack the manifold and allow for a vacuum leak. However, with the screw in, the leak is supposed to be sealed well enough for the motor to run perfectly