EGR-BPT testing outcome

[zer0c123]

I followed the procedure to test the BPT on the 240sx.org tech page

1. On one of the top two ports, attach a vacuum pump
2. Plug the other top port
3. Gently blow into the bottom port

The pressure gauge held constant when I did the above steps. Now here's the thing, I stopped blowing air on the bottom port, but still held 1 of the top ports closed. The instructions said that air should leak out, but once I stopped blowing air, the pressure gauge immediately went to zero. That does not look like "leaking" to me. It somewhat makes sense to me because it's supposed to back pressure, so it should hold a pressure and gently leak. right?

[yukon]

i have a new bpt and it immediately goes to zero. it has breathers on the side. how much is your egr valve lifting when you rev engine

[zer0c123]

Well from what I could see and feel, the egr valve only lifted a little.

My current BPT is about 5 years old. The reason I was asking about the BPT test is because I have an old BPT that passed the smog test 5 years ago. On the old BPT, using the procedure in the first post, the air leaks out slowly once I take my mouth out of the bottom port and stop blowing air.

If I use the BPT valve that immediately goes to zero when the bottom port is unplugged, the Egr valve displaces a little. It's difficult to to distinguish the length of displacement from reving th engine at different rpm's

If I use the older BPT that slowly leaks pressure when the botoom port is unplugged, the EGR valve displaces a lot. ALso the different displacements are easily distinguishable from the different rpms. I actually recorded this on my phone, so I can post a video in a little bit.

[zer0c123]

need to bump this old one

[92coupe383]

ok i know this post is super old , but im in the same boat, my valve goes straight to 0 when presser is removed from bottom port, as far as i know my car has the original valve and egr, are you guys using OME parts from Nissan? also my car wont pass smog lol