Hello,
on my 94 turbo sedan I'm having an issue with boost. At times the car will boost fine, right up to about ten pounds while other times it only wants to hit around 5. From what I have read I am thinking either the tcv or the cbv. Stage 0 is up to date. The only thing that is different is where I have gotten gas. Any help is greatly appreciated, thanks.

 

no one ever had this problem?...

 

there is no one that has had this issue? starting to feel a lil ignored on this site because i can't get an answer on any posts...

 

I would check or replace your TCV lines, and your intake lines they could be collapsing under boost, I had the same problem, I did complete stage 0 and undated my lines and hoses, maybe run some injector cleaner through it.

get silicone it's worth the $$

 

You may have a blown pipe that opens up under pressure. The most common is the hose that goes to the throttle body, under it where the IAC line comes out. That will cause erratic boost.

Follow bbiljah...get silicone.

 

okay ill have to inspect all the piping. i replaced my tcv lines with silicone already so i think they are all fine.
bbiljah: what brand of hoses did you go with? i know there are a bunch. i was leaning towards samco or just the ipd ones, but i am very open to suggestions

 

Volvo Intercooler Hose Kit (850 C70 S70 V70) Silicone Blue | FCP Euro

 

My wild guess is a vacuum line based on past Porsche turbos boost issues.

 

my vacuum lines are good. i checked them out

 

Maybe a ripped diaphragm ?? Or a malfunctioning BCS that's sticking ??

 

is there a way to test the diaphragm while on the car? i dont have access to tools while at school

 

in all honesty, i am going to try and replace both the cbv diaphragm and tcv considering there probably original considering the vacuum lines were