I'm having a problem with my Manual Boost Controller. Whenever i floor the car in 3rd gear I think some sort of fuel cut off kicks in and it feels like the car hits a wall. This even happens when the MBC is turned down. My current mods are just the Controller and a cone filter, everything else is stock. When I asked a buddy about the problem he said that I need a tune for the Controller to work properly.

It sounds like this person was having the same problem as me:
https://www.evolutionm.net/forums/sh...d.php?t=194197
This thread never says what the solution is besides change spark plugs and I've already checked mine and spark plugs defiantly aren't what's causing it. Can anyone point me in the right direction?

 

Bump?

 

your buddy was right you need a tune!

 

How much boost are you running and how do you know "spark plugs defiantly aren't what's causing it"?

 

did you turn up the boost after you installed it? which mbc did you get? what tubes did you used? there are 2 ways.

 

i doubt it is/was your spark plugs

its a boost/fuel cut.

the boost tables in your map needs changing just get a tune, its probably the cheapest mod with the best results.

 

I'm not sure what kind on boost controller it is because it came with the car and it has no brand labels on it. I know its not the plugs because at half throttle it works fine and I pulled one of them out that it looked ok. If I get the tune, will I be able to use the boost controller without the sudden jerk/fuel cut? Also, once I didn't let off the gas as quickly when it jerked and the check engine light turned on and the code read overboost.

 

once u get it tuned it will work fine...

IMO change that MBC..

get and EBC or MBC

 

Get a GM 3-port instead for $50 only, beats the Greddy AND Hallman put together. (especially when it comes to price) Performs good (if not, better, than those two also)

I have it and wished I got it sooner, but then again, I'm not complaining since there's no need to adjust boost when switching maps for pump or race gas (unlike a ebc, where have to push some buttons to raise the boost up or down and/or with a mbc, where u have to turn the knob to raise the boost up or down)

U can still change ur boost settings though through ECUflash.

Check out a good link about the GM 3-port:>>> https://www.evolutionm.net/forums/sh...d.php?t=276674

 

Okies.. here it is.

Ive faced the same problem last week and i just couldnt sleep! LOL!

First, you have to choose out of the two ways that are known to get your MBC installed.

Second - You should have a boost controller to tell you how much you are boosting. Otherwise, its no good.

The reason i had the same issue was bcoz my MBC wasnt holding boost at all. My friend had played with the spring inside it and had placed the ceramic ball inside it the wrong way. This allowed no restriction and let flow boost like crazy!

As soon as i hit 3800 - 4000 RPMs in 3rd gear, i wud have the boost/fuel cut. Then i noticed the boost guage hitting more than 30 PSI... This is what kills ur engine when u reach that numbers. U dont have enuf fuel at that levels and ur injectors run out!

So the best thing to do is get ur self a boost guage. And yes, please mention what MBC are u using.. this will help a lot. My guess is you have installed the MBC using the WGA and TURBO nipple.. let us know..

Best of luck!

 

Like I said there is no brand label on the MBC, For all i know the previous owner could have made it himself. I took a picture of it.


Its connected between the vacuum line coming from the wastegate and into a T that goes into the BOV and somewhere else. When i took the piece that turns out there is no spring or ceramic ball inside, Its just like a screw. If I just take out the MBC and reconnect the vacuum lines with a coupler will it still boost/fuel cut?

 

OMG.. what is that thing?? please buy a good MBC.. that looks like it was bought on ebay.. or made at home... sorry, but never seen such a thing

 

dude.. not gonna jump all over your thread, but there are good MBC's on here for like $60>... Forge, Hallman, etc...

 

That looks like a Dejon MBC. I would go with a GM 3-port, with this solenoid controling boost and tuned properly, you'll never have to clean it or adjust it. It will control boost based on load.

 

1st off i hope u have a boost gauge to read wut kinda boost ur puttin out... i had the same problem myself when i 1st bought my car but it was wit the stock boost solenoid... it wasnt the solenoid itself but it was the vacuum lines that were cracked... i think ur best bet would be to check ur lines and get a tune, and an exhaust kit so ur car can breathe a lil easier... hope this helps