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BOV not working

5.8K views 28 replies 6 participants last post by  Bigwelly  
#1 ·
I just installed a turbo smart kompact bov on my 2017 st and I’m not getting any bov effect. Any ideas of where I could have gone wrong? It took me a good bit of time and I don’t claim to be the best mechanic but I was sure I had everything right. Thanks!
 
#3 ·
Like buddy above said, also you need to build some boost for it to blow off as well. The BOV needs some pressure built up.
 
#9 ·
Sounds like you're not going to like my suggestion, but you may want to check the hose connected to the nipple of the bpv/bov to see if there are any tears in it or that it's fully seated and clamped on. Another possibility is if the little o-ring fell out... That happened when I first installed a Boomba bpv and I found it on the garage floor a day later; after I rtv sealed the dumb thing. I had to remove, clean, and replace it after that mess :p

Are you running 'true vacuum' from a symposer delete, or just straight through the boost control solenoid?
 
#10 ·
Sounds like you're not going to like my suggestion, but you may want to check the hose connected to the nipple of the bpv/bov to see if there are any tears in it or that it's fully seated and clamped on. Another possibility is if the little o-ring fell out... That happened when I first installed a Boomba bpv and I found it on the garage floor a day later; after I rtv sealed the dumb thing. I had to remove, clean, and replace it after that mess :p

Are you running 'true vacuum' from a symposer delete, or just straight through the boost control solenoid?
Unfortunately I think that’s my issue…I definitely did not put an o ring back on when installed factory bpv. I noticed the o rings were pretty much pushed in on the kompact bov I bought. It’s a separate piece for the bpv? I guess I will need to look around my driveway maybe somewhere inside my engine bay haha. Otherwise I’ll have to wait and order the right bov valve or find an o ring replacement.
 
#11 ·
The stock BPV doesn't use an o-ring. The bottom part is just a rubber gasket type plug if I recall correctly. I was referring to the after market bpv.

If you introduced a leak with the stock bpv, and (as you mentioned) the bracket was correctly installed on top of it then it's not likely the source of the leak. Not saying it's not, since I realized what a cheap piece the stock BPV was once I replaced it, lol.

Sorry for the late reply on that. I hope you got something figured out in the meantime.
 
#12 ·
The stock BPV doesn't use an o-ring. The bottom part is just a rubber gasket type plug if I recall correctly. I was referring to the after market bpv.

If you introduced a leak with the stock bpv, and (as you mentioned) the bracket was correctly installed on top of it then it's not likely the source of the leak. Not saying it's not, since I realized what a cheap piece the stock BPV was once I replaced it, lol.

Sorry for the late reply on that. I hope you got something figured out in the meantime.
I haven’t figured it out yet but I did get a dual port bov ordered so I can at least put that in to see if there are any leaks. Will driving my car with the leak for a couple days be okay?
 
#17 ·
I just tightened up a few of the bolts holding the bracket on and am still hearing a blowoff type sound every time I come off the gas pedal. made sure the airline was tight and everything, I just feel like im not hitting the boost I had before I started screwing with things. What is the average amount of boost I should be getting when I am really opening it up? Im seeing maybe 10 psi in lower gears. Thinking about taking it to a shop. I also may have cross threaded the bolts when bolting the factory bpv back on could this have effected anything? thanks
 
#21 ·
Yeah the green filter absolutely will allow you to hear the bpv.

Video would help confirm.
So I took a video revving the engine in the driveway and there isnt a pshh type sound I have been hearing while driving and shifting through gears, I guess I will have to try and capture the noise while I am driving. Unless I was just hearing things all along? and I think I was just misunderstanding amount of boost pressure through the gears, I was able to get about 15-18psi going from 5-6th gear at about 3k rpms. Obviously I can't know exact numbers since I don't have any type of monitoring system or access port.
 
#26 ·
That sounds pretty stock to me, with some additional sound (probably due to the dual sided Green filter). The release is precise and longer than most aftermarket bpv so I think that's not your main issue for the lack of boost at all.

Have you messed with the FMIC at all? Lots of hoses between the intake and the turbo like to leak a bit...