Manual boost control not working

[kreature]

I added a small bottle of "Liquid Nitrous" Octane booster to 15 gallons of 93 octain gas.
Ever since my boost has been at 20 and thats not good for me, above 20 and I get fuel cut. I've run that gas out and filed up since but still the same thing. I can't turn my boost down, I use to be able to adjust from 10 to 20 and now I can't do squat but watch my boost gauge to be sure I don't exceed 20 psi.
What's the deal?

I havea 91 Mitsu eclipse GSX with: high flo injectors, a racing fuel pump, Super AFC, 95 talon pistons, bigger turbo and 3" Bucher racing exhaust.

 

[Spoolin4Ever]

Make sure the lines connected to the MBC are not reversed (wrong hose on each side, switching them fixes it).

 

[oldman]

Disconnect the mbc and run the pressure source directly to the actuator. If problem persists, the actuator is most likely not opening. If problem solved, mbc is defective or hooked up incorrectly. I doubt this has anything to do with "Liquid Nitrous" though I do not know enough about "Liquid Nitrous" to be 100% certain. Good luck.

 

[projektlaser90]

I Have a friend who has a 95 Talon TSi and the same thing happened to him. In his case though he had his boost controller open too wide and the ball bearing inside the controller fell out so maybe the same thing happened to you i would take your mbc off and check it if you can. you may have to get a new mbc

 

[kreature]

Disconnect the mbc and run the pressure source directly to the actuator. If problem persists, the actuator is most likely not opening. If problem solved, mbc is defective or hooked up incorrectly. I doubt this has anything to do with "Liquid Nitrous" though I do not know enough about "Liquid Nitrous" to be 100% certain. Good luck.

I'm pretty sure the MBC is fine, ball is in there and spring and everything, now, where do I get a new actuator?

 

[patsdsm]

you either have a cracked wastegate flapper houseing or your wastegate is just messed up

 

[oldman]

I'm pretty sure the MBC is fine, ball is in there and spring and everything, now, where do I get a new actuator?

Junkyards, turbo vendors, classifieds...etc. Just double checking, are you sure it's all out boost and not boost creep?

 

[punishercb]

I'm pretty sure the MBC is fine, ball is in there and spring and everything, now, where do I get a new actuator?

Still you might want to just check it. The same thing happened to mine too. The ball bearing didn't fall out or anything but it was backed out too far. I just screwed it all the way and then backed it out until it worked right again.