Can't get past 10 PSI

DId some research on this, but I am just confusing myself. I was adjusting my MBC to get more boost. The thing is I can't seem to get past 10PSI. My MBC is kinda old and difficult to adjust. It doesn't look closed all the way, could that be the problem or could it be more serious.

Any help is appreciated.

is it a stock turbo?? because i thought the stock turbo's only run 9psi, might be wrong though..

A stock 2g runs around 9-12psi depending on wether it had the bsc removed or not. However with a boost controller it should be able to go higher. It could be that your MBC is not funcioning correctly or that it was not installed properly. Check the installation procedure on www.vfaq.com and make sure its correct

Hey thanks Engineer. I couldn't find a good write up on the vfaq. However, I did look on this forum and I found conflicting arguments. I am not sure if the MBC is setup optimally, but all that aside, I believe the MBC is 'sorta' setup right becoz I can reduce my boost. I've gotten it down to 4 or 5 psi using the MBC.

I think I am going to spray it with wd-40 or something and see if I can get it to close all the way. If that doesn't up my boost...then what?

Thanks

Also, I will let you all know how the MBC is setup soon. haven't had time to really look at it. Friggin work sucks! lol.

well here is the thing. There is no way you should be able to get your boost down that low. If you turn the boost down like that the stock Wastegate should take over to control the boost which i believe is something like 8psi or around there. I could be wrong but i believe something is hooked up wrong. What does your boost guage read at idle.
 
Also here was the article from vfaq that i was talking about.
http://www.belitski.com/cars/talonmods/turbo/vfaqhallman.html
 
I think the conflicting arguement you were talking about is where to tap in the other end (not the wastegate end) of the MBC. The how to on this link says to connect to the BOV line which IMO isnt the good way to do it. Just connect the other end to the nipple on the compressor housing of the turbo.

im havin the same problem but i cant boost past 7 maybe ur turbo is crappin out on ya like mine is or maybe you have a big boost leak what size turbo are you using

I'm running a stock turbo. :[ Is yours stock too. Thanks for the links Engineer, I'll check it out and look under my hood to tell you the setup.

Where is your boost gauge taped at? Manifold or at the wastegate? Reason i ask if u happen to have any kind of boost leak and the gauge is at the manifold it will read the boost you get at the manifold not the turbo. Also are you pulling boost reading when just revving the car or under load? My car will not give proper Psi unless it is under load.

It could be your blow off valve.. Are you running a stock bov?    

Ok so my noobness is going to shine here. Lol

Advocate, I am running a 1G BOV

My gauge is T-off at my manifold.

My MBC is tapped at uh, where my lower intercooler pipe meets the turbo?
And then, i'm not sure, but somewhere underneath my intake. I am assuming the wastegate which looks rusted like ****.

I dunno if the first tap makes any sense. But that's what I see, I even have a pic.








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thats an interesting place to tap the MBC. The second one must be going to the wastegate. But that one to the IC pipe, i guess that should work fine.

So it sounds like it's not optimal.

Could I be getting the wrong readings (as in lower reading) from my gauge since it's at the manifold? I guess what I am saying is, could I be running like 9psi but my gauge is reading 5-6psi and then running like 13psi but my gauge is reading 9-10psi? I mean to me that would explain how I decreased my boost so low.

Also, get435(?) I have not checked whether I am running boost under load or not. I'll get back to you.

Also, I guess I should remove my wastegate and see if it's working properly? From what I can see it's rusted out like ****. Haha, I love cursing, make the server work! to post the asterisks. lol

Thanks

The wastegate is not the thing you can see. The wastegate is internal in the turbo. What you  see is the actuator which controls when to open and close the wastegate. That is another posibility is that the rod on the actuator is stuck and not moving the wastegate flapper

Ok, so I will look at the actuator when I get a chance. Thanks for the info.

Also, I haven't looked to see what my gauge reads at idle. I'll post that soon.

In regards to my other question about the gauge reading, is it possible? Could I be getting the wrong reading (a lower reading) from my gauge since it's at the manifold?

Ok, so on idle I get about 25 InHg.

When I rev it I go to about 10ish InHg and then it goes back to the 20's. So I am only getting boost on load.

So if I take my actuator off what should I do to check it? Or can I test it while it's on? Spray it with wd-40 or something?

Ok, so I took off my intake and noticed the tube from my mbc to the actuator had a big hole in it. I fixed it. Would that be the problem? (Took some other parts off so I can't run my ride right now) So would that have been my issue (i know we are just guessing here) or should I just remove the actuator and whatnot?

Thx

that hole in the hose could have very well been where your issue was, boost leak

That would definetly cause problems having a hole in your line. Hopefully that fixes your problem

Thanks all. I'll just work on the other parts and test it when I get the ride running again.