So I noticed that my car was not holding boost, to the point where the turbo was barely spooling. So I decided to do the tennis ball vacuum leak test, and can most definitely hear a leak somewhere under the headers. After listening and searching for where the leak is coming from, I still cannot manage to pinpoint the source. I know that shops do the smoke test to figure out where the leak is coming from, but I was wondering if there was someway to help me pinpoint the leak without having to dish out the money to have a shop do it.

 

take your pick...

 

I've used soapy water before with pretty good success. Especially since you know the general area of the leak. Just be careful about what you spray it on.

I'm a bit confused about where you're referring to though. By "headers" do you mean the exhaust manifold? If that's the case, sounds like you've got a leak somewhere in/on/around the turbo. Maybe the wastegate or N75, or something attached to the turbo inlet pipe.