2004 S
the black curved tube is your dip stick tube, it is flanged too the block with a single bolt. I can't recall how far into the block the penetration goes. The complete dipstick tube is two pieces, this pic is one piece and the 2nd piece starting in your trunk is the plastic piece.
The oil dipstick tube in your trunk , which is plastic, attaches to the end of this tube (in pic) over the collar by a pressure fit clamp, squeeze together between your fingers the 2 grey buttons of clamp.
Threaded Mode
