i have a evo 8 had bad idle did a leak test through the TB and located a leak on the shaft seals so I replaced my TB seals and screw oring they were pretty beat up so it fixed the idle somewhat now I run rich at idle, it goes all the way to 12 stays for a about 15secs then drops all the way to 17 then slowly climbs to 14.8 could I still have other leaks or is it tune issue ? had shop tell me I needed to get it tuned but I can still hear a slight hiss around the intake manifold or I could just be hearing things

is their anyother parts around their that go bag like the shaft seals

 

why not test the whole system from air filter to motor for boost leaks? that will tell you a lot. make sure you plug up any small hoses like PCV valve...


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