Here's an image I took of a metal tube which bends around under the intake manifold. I discovered it to be loose enough to rattle up and down with about .5" or more of play. Should it be loose like that or nice and tight? Also, what is it?
Thanks in advance.

 

It is cooling and part of the crank case vent system. The end bolt on the intake should hold it into place.

 

Ok, thanks. I'll get it looked at.

 

It is part of the Crankcase ventiliation system (PCT. I wouldn't worry too much though unless it's really loose. They are all pretty loose, the other end of the pipe connects to a small black hose with a clamp on it that goes to the intake pipe.

When you install the Snabb intake this pipe connects to your PTC element.

 

Cool, and thanks. I won't sweat it. The car is running fantastic at the moment in any case.
I had noticed that loose tube, thinking it to be either EGR or PCV related, and wanted to rule it out from problems the car was having.

I had been getting intermittent rough idle and check engine light every week or so, even after cleaning the MAF and changing the fuel filter... followed by new Denso IK22 plugs and IPD's high quality ignition coils. A few days ago I swapped out the Bosch F/A upstream sensor (had to splice it in), and it's been running perfectly, though too early to tell yet if that fixed the intermittent problem. Fingers crossed it was only the upstream sensor going flaky.