Ok guys when I start my car, the vac acts like it is breathing in and out, goes from 15 to 20 back to 15 back to 20, does this for a little while.
After warmed up and running it sets 20 at idle...
idle is ruff kinda...exhaust has an unsteady sound, rpms at idle are steady.

Any ideas?

 

hmm....have u checked for vacuum leaks, although idk if that would be issue if it settles out after a while...

-check your air intake
-check for vacuum leaks
-run some fuel system cleaner
-seafoam the engine

hopefully that helps, i think the seafoam will do more for your car than the other things will...

 

ok done fuel system cleaner, done seafoam...
i've sprayed around to check for leaks, no change in idle...
I do hear an almost hissing sound from lower drivers side of engine....can't tell if it's front or rear...hell maybe its my h/e waterpump running sound...can't tell, but it is a hissing type sound.

Anything on lower drivers side that could be a vac leak?

Would the s/c gasket leaking cause that?

I do know during boost i never hear my sc at all, i did used to..

s/c has been taken off the car before and put back on the same gasket.

 

You don't hear the s/c at all......are you losing boost at wot? You probably just answered your own question, I am betting s/c gasket.

 

When I go full boost it's up there but the car will act like no boost is going on then all the sudden kick in, or not...it kinda does its own thing when it feels like it, even showing full boost and all on it, I don't hear the whine.
It's more of a deep sound, almost like my 2.2 sounded when I put on the gmpp sri and would dump on it.
Deep low sound.

FYI I get like 33mpg average.

i can say it seems like when in boost not wot holding steady i lose boost....

Could also be my car pulling timing...why i dunno....
wtfknow...i just about have gotten to the point where i hate my car...

 

could be the bypass actuator or a leak in that line?

 

bypass actuator is the one on the actual sc right?
Would this also make the car kinda run crappy?
Choppy idle or anything?

Vac lines have been replaced.

boost bypass mod doesn't fix the problem.

should actuator be open on startup at idle then closed when car shut off?

 

Boost bypass actuator is shut when car is off, with car on at idle it is wide open...
If I close it with my fingers the blower makes a pretty crazy grinding type noise.

So 2 questions, should this actuator be open on idle or closed and if it is suppose to be if you close it at idle does anyone elses s/c make that sound?

Thanks!