So i took the car out for a quick spin and when ever my car began to hit boost it would make a fluctuating choo choo sound from the BOV. I opened the hood and heard a large leak by the throttle body right by the BISS screw. My question is when people say their BISS screw is leaking do they mean air in coming out from that exact location;the screw. This leak comes from the side right next to the screw location, however if i tighten the screw the leak almost goes completely away. The car idles fine, but i haven't been able to take the car out again. I plan on going to Home depot today and chang out the 0-ring. It just seems strange that a bad BISS o ring would affect the boost this much yet the car idles completely fine.
You need to do a pressure test as well... chances are your TB shaft seals are shot. And yes, the o-ring becomes rock hard where it doesn't seal within the port. When you tighten it all the way down, you are actually blocking the opening with the screw itself.
Well i removed the TB and found the gasket to be on wrong and fixed that. That leak went away. I also tightened all the IC pipes,and switched out/greased the O-ring on the rear turbo. I still have the strange hooting/choo choo noise. If i go WOT i don't hear it, but if i add partial throttle it fluctuates, getting higher in pitch as rpms and boost builds. Also when the BOV does goes off it sounds alot more high pitched and audible than it did before. I plan on pressure testing as soon as i get home to my compressor. but that wont be until Wednesday.
i have an evo 9 BOV and have had alamo SMIC. I actually just had 15g's put on the car by a reputible shop, but they were having issues tunning with the flashed ECU. Basically the front bank was adding fuel while the rear bank was removing fuel. They put in the stock injectors and ECU and told me to break in the clutch then bring it back to tune once i got 400mi on her. I think i may know what the problem is though. I bought those upgades wastegates from Drweldin, and i dont think they were tuned to release at the same time. The turbos are probably 'fighting' each other under partial throttle, and im going to assume this would also affect the strange fuel readings.
Well now that im home i was able to pressure test the car. The only leak is comming from the passenger side. I have checked all the connections on the alamo hardpipes, but cant get rid of the leak. i even used the soapy water method and cant find it. The only other thong in that are is the clutch vacuum tank, but i doubt thats whats caousing my problem.
The AutoGuide.com network consists of the largest network of enthusiast-owned enthusiast-operated automotive communities.
AutoGuide.com provides the latest car reviews, auto show coverage, new car prices, and automotive news. The AutoGuide network operates more than 100 automotive forums where our users consult peers for shopping information and advice, and share opinions as a community.