MBC not working! WTH?

[BoostMonkey]

Alright guys, I'm using a manual boost controller that I bought off of ebay (yeah, yeah, probably my problem) awhile ago. It was a very reputal dealer but today when i went to install it, no matter what I'd do I couldn't even get it below boost cutout. I took it apart and made sure the ball was seating (it was), the spring is putting barely enough pressure on the ball to seat it with the screw all the way out. Everything seems to work as far as the controller.

But what the hell did I do wrong? What I did to install it was run a vacuum line from the wastegate to the proper nipple of the controller, then ran a line from the other nipple of the controller back to the vacuum line that went to the wastegate. For now I just put another connector inbetween the two vacuum lines so it's back to stock settings. Any Ideas?


Michael

[deuce dodge]

grainger

deuce

[MoparN75]

need to use a vacuum source off the turbo compressor housing {where cruise line goes} or off intake. You're going throught wastegate soleniod and that won't work, that line will need to be plugged.

[Dave]

Wait, youre running a vaccum line to the MBC and from the other end youre going back to the wastegate? Yah that's like running an open wastegate. You probally saw upwards of 18psi didn't yeh?

Run one line from the WG can to the MBC, and another either to the nipple of the turbo, or to the intake manifold.

[BoostMonkey]

Okay, I gotcha. I was under the wrong impression that the Wastegate ran off of vacuum so using the vacuum line going to it wouldn't hurt. guess I was wrong huh? lol I'll let you guys know how it goes here in a little bit. Thanks guys!

Michael

[JDAWG]

and get a grainger, I got an ebay mbc at first and no matter what it would hit cut out

[BoostMonkey]

well guys, I really need help now. I installed it properly, but it was still hitting cutout. So I think the MBC is screwed up. So I put it back to stock, and now I got a stumble problem under WOT.

When under WOT, the boost will hover between 10-12 psi, and it'll have a couple minor stumbles (2-3) then the boost will spike to 14 psi and it hits cutout. I've checked and rechecked all my vacuum lines that I've messed with, and everything seems to be okay. I noticed though that my 02 sensor wires look a little baked and I did smell something burning. Yet my check engine light isn't on. Any ideas?

Michael

[BoostMonkey]

UpDate: Had a bad vacuum line that I just replaced, and everything is hooked up correctly. I tried hooking up my wastegate to a different vacuum line coming off the intake. When I did this, it'll hold boost at a STEADY 5-6 psi. So, is this a problem with my wastegate? Can I install a grainger and still get it to 11-12 psi even if right now it's only at 6 psi?

Michael

[Dave]

So you get 5-6psi with just a vaccum line running to the intake? If that's what you're saying than yes you can install a g-valve and get to 12psi.

It shouldn't be doing that... you neglected to tell everyone else you have a TIII motor... stock boost IS 11-12psi. Try the g-valve, but be careful, the TIII motor's fuel supply is a lot more limited than the TI or TII's.

[BoostMonkey]

Yeah I get 5-6psi with the wastegate running to a vacuum line from the intake.

[Dave]

Yeah I get 5-6psi with the wastegate running to a vacuum line from the intake.

*pukes* G-VALVE THAT THING MAN!