I'm in the middle of my S15 build and don't know where this thing goes. It comes out of the fusebox somewhere. Any help would be appreciated, sick of wasting time on stupid things like this!!
looks like the boost pressure sensor, for the interior gauge? sits on the left hand strut tower (as your looking at it) looks like its missing the mounting bracket.
can see it in this photo,
can be seen on the second photo down on this link http://www.sxoc.com/vbb/showthread.php?528921-S15-Spec-R-boosting-high-why