Basically i connect it to the turbo intake and fill the system with air to spot for leaks

Well 2 things evo 9 bov opens at 10 psi to let air out so i flip it to close it and create a seal.

2nd i hear air coming near the throttle body on the black part where the spring is located if i press on it a little the air leak is quieter. All this done at 20 psi due to failing boost leak adapter for turbo


Or is there a different way to boost leak test? If I connect it to the turbo till fill it with air should it hold the pressure with no air leaking, or will air escape anyways but really slowly where its not noticeable?

 

Just read a few how to's i did use soapy water and did bot see bubbles from the throttle body, but im guessing the air noise is normal?

 

Stock BOVs are known to leak... some worse than others but that's the reason I went with a Synapse DV. I tried 3 Evo 9 BOVs and all of them started opening before I wanted them to. The leak on the throttle body is the throttle body shaft seals leaking. This is also very common. Several companies make throttle body shaft seal replacement kits such as Mil.Spec.

So in summary, you need to get a new BOV (I recommend the Synapse DV) and some upgraded throttle body shaft seals. If you're on the stock MAF make sure you get a DV that recirculates. VTA BOVs and the stock MAF usually don't get along very well. Hope that helps!

 

Air will still escape slowly through the head but it sounds like you did it right.

 

+1

Have you tried this how to?

https://www.evolutionm.net/forums/ev...g-how-why.html

 

^WOW that is a lot of leaks LOL

 

Yea i saw his video last night and did everything he did.

Looks like i need a new bov and tb shaft seals

Thanks guys!

 

yeah my stock IX bov leaked around 20psi, got a synapse. The VIII bovs are different (plastic vs metal for the IX) and leak at even lower pressures. Also, it's common for the small vacuum lines that go to the intake manifold to pop off, so make sure to check those. I ended up putting zipties on all of them about a year ago and haven't had an issue since.

 

That's exactly what I was thinking.

 

Did the guy use soap water in the video? I will try this tonight.

 

Don't forget to use a good amount of zip ties