As I did the boost leak test with my own tester, I heard hissing from many sources. If you plan to do this test, google “boost leak tester” for more info on this.
I had these places hissing as i forced air into the intake. Action taken in parentheses:
- Blow-off leaked – really cheap crap that needs to be replaced (new blow-off from Greddy)
- Blow-off / intake pipe seal was leaking (needed tightening)
- Throttle body shaft seals leaked (replaced)
- Injector O-rings (replaced injectors along with the O-rings)
- BISS screw O-ring (new OEM parts)
From this site you can order the seals: http://www.machv.com/throtbodseal.html
helpful link with step-by-step instructions Link
TB shaft seals
Fuel rail, ISC, injectors, throttle body, TPS
Throttle body shaft seal location
Crappy replica of Greddy Blow-Off starts to leak at 7PSI