Tank Pressure Sensor 3 way joint

[aklackner]

So I think I have everything I need to get my gas tank installed....except I'm struggling with 17357-S02-L01, #5 in the diagram below. I'll call this the fuel tank pressure sensor 3 way joint.

I know one side connects to the fuel tank pressure sensor (#1 diagram below). Another side connects to a fitting (#4 on diagram) which is mounted on the frame rail. I can't seem to find anything to give any indication where the third leg of the joint connects.

Since the purpose of the fuel pressure sensor is to measure pressure inside the tank it seems this hose is the source for atmospheric pressure to determine relative pressure from absolute tank pressure. Given this I understand the purpose for a line going to the frame, but I can't understand why that would T (or Y in this case). It's orientation almost looks as if it could be a drain for condensation or in case the frame is submerged? But why route to the frame at all if leaving an end open (uncovered\filtered) and the purpose is only as as source for atmospheric pressure, why not just leave the sensor nipple open if this were the case?

Is the third leg simply left open or does it need to be routed somewhere in addition to the tank pressure sensor?

Relevant Helms pages (11-141 '98 update, 11-101 '01 supplement, ironically the best illustration I've found is the parts diagram below)

Unfortunately all is located under the shield (#9 on diagram) on the front left side of the tank so installed visibility will be limited but I'd be grateful if someone ('98+) could take a look and trace or confirm if the third leg is open.

[aklackner]

Also some info here (CRV seems to have same evap setup)
https://www.autozone.com/repairguides/E ... 528026a70f

[Stin1]

I was just under number 9 changing my valve this weekend and I saw number 5 not attached to anything on one side as well. There was nothing to attach it to. I wouldn't see any reason why someone would remove it but anything is possible.I also accidentally tugged the line that attaches to the one side of 5 off the chassis. It's didn't seem to attach to anything beyond the chassis. Seems like it was for fresh air. Maybe for the swoosh you hear when filling up ? I could be wrong.

[aklackner]

I was just under number 9 changing my valve this weekend and I saw number 5 not attached to anything on one side as well. There was nothing to attach it to.

Great, that's what I was suspecting, even if it's supposed to be connected to something I'm pretty sure it's just fresh air\atmosphere. That means, if something is left unconnected, at worse your risking whatever that would be clogging (or siphoning if driven in deep water, probably not going to be a case for most of our cars at this point)

[Stin1]

IMG_3973.jpg (77.38 KiB) Viewed 1132 times

Some eBay auction, had this picture. I think it's like mine. Same deal at least. It was listed as multiple years. My 98 has it as # 6 , not 5 .

IMG_3974.jpg (85.84 KiB) Viewed 1132 times

[98DC2R]

I replaced one of these just the other day on a friends 98 ITR, the 3rd leg is left open, even referencing my 1998 Integra helms manual it shows the other side vented to atmosphere. #4 shows sensor joint which I believe is a one way relief valve if I remember correctly. if I get a chance Ill put my 98 on the lift and verify.