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Half Boost PCV issue?? please help

Damon318

Damon318

New member
ok this has been a headache for a long time and i really need some advise. i have a 98 gtp cai u bend delete other than that its stock. i have super hard crank case pressure which led me to the pcv i replaced it twice including all orings and i cant get it to stop squealing from crankcase pressure. i have half boost and odd issues with my rpms when im cruising and let off the gas. i dont know what else besides the pcv that can cause crankcase pressure? other than the low boost and crankcase pressure everything runs great? any help would be greatly appreciated.
 


well, first off.

rule out the Boost Bypass Solenoid as the reason for 1/2 boost.

disconnect the boost/vac line on the BBV (bottom) and plug the line that was feeding it so you don't introduce a vac leak.

and unplug the harness... your BBV should stay constantly closed now.

see if that affects your boost.. if so you might have a poopy BBV or wiring issue.
 
Alright I went out tonight to rule out the boost bypass and noticed two bad vac line couplers! I'm going to replace them in the morning and I really hope this fixes my issues! Any ideas on the crank case pressure?
 
I feel kind of dumb now, couldn't the vaccum leak be causing the PVC to malfunction because of low pressure? I think I may have fixed the whole issue? I'll update in the morning when I get the lines fixed
 
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ok i fixed my vac lines and im getting all but two bars of boost ( double what i had before) and yes i have the spring and o ring on the pcv but it still squeels! i dont know what could be the problem? i also tested my bbv its running fine
 


one more to add i changed my supercharger oil and now im getting full boost so one issue down one more to go!
 
tylerbinski said:
sweet man.. did that stuff stink? :th_radioactive:

haha
Click to expand...

Yea it was pretty nasty stuff! But it helped a lot. Do you have any idea why I am still having the crank pressure? Even after changing the pcv? No codes and I just leave my dip stick out ( to relieve the pressure) and it drives fine but I really want to fix the issue
 
lets try to narrow this down a bit.

the pcv system has 2 parts.

1) suck out crank case gases etc (input to Pcv valve)
2) allow fresh air into crank case to replace sucked out air

if number 2 is not working, you will be creating vacuum in the crank case and air will be flowing INTO the oil dipstick hole to replenish

I suspect that might be the case...
otherwise you could have larger issues if you have pressure in the crank case.. could be caused by poorly sealing piston rings (blow-by)

try and cover the dipstick hole with your finger while in park and figure out if its blowing or sucking.
 
Pressure usually means the pcv isn't functioning. Aka it's blocked, the SC gasket wasn't cut for the pcv, an intercooler is blocking it etc.
 


the dipstick is definitely sucking air in. so what could be my issue where would i start ive replaced the pcv and o-rings im not sure what to do next i havent had my SC off and i am stock other than my few mods listed. is there a way to track down which part of my pcv system is having the issue?
 
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