Signs of a leaking bov?

[GST2G]

bouncy idle? low vac? low boost?

 

[Generation1JeY]

leaky at idle or leaky at boost? some BOVs leak at idle, and dont at boost, some leak at boost and dont at idle.

If ur talking about leaky at idle, if u have it recirculated then u wont notice it, because there is no air leaving the system, so u wont have a vac leak because it just comes back around. on the other hand if u have a vented BOV and its leaking at idle, then yes it will make ur idle fluctuate, it will make u bog when u drop the throttle, and its a simple vac leak so it will make ur vacuum decrease. FYI almost all 1g BOVs leak at idle, thats the main reason why people have problems when they vent them, they think its the process of venting it that messes the car up, but its actually just the BOV, if u have an aftermarket BOV that u can adjust, or is just naturally stiffer, then u wont have any problems except for the rich shifting conditions.

 

[steve]

FYI almost all 1g BOVs leak at idle, thats the main reason why people have problems when they vent them, they think its the process of venting it that messes the car up, but its actually just the BOV.

1G BOVs are designed to open when there is a 7.7 psi difference between the lower half and the uper half of the diaphram.
That works out to a manifold vacuum of about 16 in hg causing them to open if you intake is at ATM pressure. Uncrushed. So all stock 1G BOVs should be leaking at idle with a normal engine vacuum of about 18 in hg. Like you said if it's vented it's a huge source of unmetered air at idle.

Steve

 

[Generation1JeY]

ya exacty what he said, but that explains why venting does it, because when its recurculated it leaks, but the air it loses never leaves the intake system, so it still remains air tight.

 

[o0GuitarKid0o]

Yenno I gotta ask and im fairly certain it's my Bov (I do have a spare to swap but havent yet and a new gasket )

This sound has happend right from the beginning


When doing a boost leak test my bov has never leaked at all due to positive pressure keeping it closed from the intake but I've had this strange issue where when I'm at 0 psi (just about to hit boost ) on my auto meter boost gauge It makes a long psshshssshshssshsshssshssh sound before I hit boost and I've noticed at even at 3-5 psi it still does it ( I still have a intake leak somewhere on the throttle body) it's super annoying because it doesnt sound like a normal blow off unless I hit 10 -12 psi . By that time I'm either speeding or just gave her hell from the red light (I dont like to but yenno how it goes ) haha

When I was driving home last night It dawned on me that the sound I hear is the exact same sound I hear when I let off the gas after boost (although it's a quicker psssh) and I hit 20 hg when that happends as usual.

My plan is to remove the vacume line on the blow off to see if the sound is the same when I do a boost leak test . Has anyone ever heard of this before ? It's like my bov leaks until I hit anything past 5 psi.

My turbo is a fully rebuilt ported 14b with absolutely zero shaft play .

One thing I should check even tho I glanced at it is a leak on the recirc tube .(doubt it)

It's like the vaccume is lagged for the bov and causes it to leak until I hit anything past 5 psi and the intake forces the bov closed .

Clogged vac line? Bad Bov? No boost leaks other than throtte body seals .

I can take a video of the sound although my speedo cable isnt working so I use my phone as a speedo until i replace the vss I even have code 24 for the speedo cable although doesnt ingauge the check engine light. Just shows up on the logger when I scan the ECU trouble codes but isnt active .

I know I'll figure it out regardless but wouldn't mind some input

 

[o0GuitarKid0o]

Doing a boost leak test after work so I'll post when I have some more info

 

[my98gsx]

100% do a boost leak test. Symptoms of a leaky BOV will also be determined by what Mass air you are running, and its location on your charge pipes. - Recently we did a boost leak test on my friends GSX, which had a surging idle issue. Once we determined the HKS BOV was leaking, we removed cleaned, and lubed it up prior to reinstalling. Now that the leaking issue is resolved the car does not surge anymore. Best of luck

 

[o0GuitarKid0o]

It ended up being bent fins from when it was stored on the exhaust side i should have noticed it when I installed it .

16g is on for now