cant go past 5psi

[shallowshowcase]

ok i removed my mbc and ran off the wastegate actuator. it wont boost past 4-5 psi. i did a boost leak test and had to put an o-ring at the bov where prev owner didnt have snap ring pliers (hks bov) and was in too big a hurry to vent his setup. i also found that the intake/tb studs in the intake manifold are stripped on the manifold side, so they wont tighten up all the way... my IC pipes however did not have any leaks.

my question is, with the MBC it would spike to 11psi and go down to 10 psi. but when i took the mbc off it wont go past 5 psi, and doesnt spike. what causes that? isnt it supposed to be at 10 psi without a controller?

 

[vr6chris]

you might want to mess with the wastegate actuator rod then. and again check for boost leaks

 

[shallowshowcase]

what do u mean by mess around with it? how do i adjust it?

 

[DSMcrazy3]

From the looks of your vehicle profile you have a stock turbo, which isn't adjustable. So disreguard his comment. He has an aftermarket turbo, so he might have just assumed.

Josh

 

[shallowshowcase]

being that i have never installed a mbc because the car came with it, i just walked backwards through the mbc install, i just needed to hook up the hoses to the bcs

 

[vr6chris]

yeah, sorry about that. disregaurd my comment

 

[shallowshowcase]

well the previous owner rebuilt the turbo before i bought it. is it possible he changed the waste gate spring? i hooked back up the bcs lines and took off my boost controller, and it still doesnt go past 5. it boosted 10 and 15 fine when the controller was on there

 

[mig233]

sorry if i'm jacking the thread. But i might be experiencing the same problem as you. I have a mbc in, and it spikes to 15 and sets at 10 psi. How do you have your mbc hooked up. The bottom nipple is connected to the wastegate actuator, and the side nipple is connected to the nipple on my turbo.

 

[shallowshowcase]

i did a boost leak test and corrected the only leaks i found (tb, and the bov o-ring needed replacing)

i havent ever checked the waste gate side before, so i just take the o2 housing off and look at the flapper, and see if i can move the actuator arm back and forth? if the flapper isnt sealing, or i can pump the actuator arm, what does that mean? that i need a new turbo?

 

[shallowshowcase]

great idea, i have no idea what your talking about

well i cant pump the actuator arm, i plan on dropping the down pipe tomorrow to see if the wg flapper is sealing completely. which bolts is it you are speaking of to tighten if the flapper isnt closed completely? where are they at?