Mbc problem? Boost issue

[ChrisDSM22]

Okay, my problem is I just installed a Joe P manual boost controller and it does nothing. My boost in first gear is solid at 15 psi but when I hit second gear it goes strait to 20 psi. Both are rock solid when they get to that psi. I have tried adjusting the boost controller and it doesn't do anything. It still goes to 15 psi in first and 20 psi in second. What is going on?

 

[csgsx23]

Not to patronize, but do you happen to have the mbc installed backwards by chance? Its really easy to do by accident.

 

[scottsee]

Sounds like boost spike/creep partner. Does it ever lower from 20psi at WOT? I have the same issue. I've tried porting the o2 housing & exhaust manifold. It helped a little. I didn't feel like spending $300 on an electric boost controler (which alot of people say works!) when my $10 MBC works great so I just tuned my car to 20psi.. It's consistent!

It's an Evo316g, let it breath....

 

[95-talontsi]

First how do you have the boost controller hooked up?

This how you should have it hooked up.
http://www.dsmtuners.com/forums/showthread.php?t=237982

 

[ChrisDSM22]

I triple checked to make sure it wasn't backwards. That is what I thought I might have done at first. I ported the crap out of the manifold, turbo, and O2 housing. I took the 16g off to be ported so the 14b is on there for now. But I just put this new mbc on and that's what it is doing. Any other thoughts?

 

[ChrisDSM22]

That is how I hooked it up.

 

[95-talontsi]

check for boost leaks

 

[gdmbat85]

make sure the stock boost control solinoid is disconnected. i accidently forgot to disconnect it when i hooked up my controller and had similar problems.

 

[ChrisDSM22]

I have always had my stock boost sylinoid pluged in just not hooked to any vac lines and have never had this problem. The way my old mbc was hooked up to the bov line and worked perfect. Now I got the new mbc and hooked it up the way it's supposed to and I'm having the problems. It acts like it is set at 20 psi when i'm in second gear cause it doesn't move at all. Same in first when it goes to 15 psi is rock solid.

 

[gdmbat85]

yes sorry, by disconnected i ment the vacuum lines are disconnected.

 

[ChrisDSM22]

Not a problem. Any other ideas on what could be causing this?

 

[bkdsm89]

mine was doing the exact thing. finially i just took the MBC out and now its running consistently at 14 lbs. but istill dont know what was causeing that to happen.

 

[ChrisDSM22]

Are you just running a hose straight from the compressor housing to the wastegate?