Over boosting on an Evo III 16G

[whitetiger777]

I seem to have a problem with my Evo III 16G. It is installed on a 2G with a Turbo Xs high performace boost controller (The one with a fine and corse adjustmets). It seems when I get on the gass it wants to go up to 20psi or higher. I have a O2 dump tube with an atmosphereis dump, and I'm not sure if I can hear it. I also had an 3in exhaust made ans it's rather lowd due to the fact that it is basical just a staight pipe with a muffler. I do not have and fuel system modifications so I don't want to run higher than 15 psi for right now, and once I do mode the fuel system I realy don't want to go higher than 18psi. Any idea why my turbo is boosting so high.

 

[onegee]

After reading your last thread about the vacuum line and now this one, It sounds ALOT like you have boost creep.

How fast does it shoot to 20psi? Where do you have the MBC set at now?

 

[mirkoelek]

i had the same problem dude....its funny and i'm pretty sure that your turboXS boost controler is hooked up backwards
Check it out and let me know

 

[whitetiger777]

Ok, to answer questio #1, it basical runs right up to 20 psi then I imedeatly get detonation. For question #2, I'm pretty sure it's hooked up right. I follwed the instructions that came with the controller. I did however switch the hoes just to check and it jumped up to 22 psi fast.... How do I spot boost creep? Also what does the sound of an atmospheric dump on an O2 sound like? Should I be able to hear it over my loud exhuast?

 

[rob_rousseau]

read the other thread you started... your MBC is not hooked up properly.

 

[dsmrunaway1]

u should be bale to hear that dump tube from a mile away.....and esp if u were hitting 20psi+...the more boost the louder that thing gets....so yea u should def be able to hear it over ur exhaust...boost leak ??

 

[Sk8er07999]

It's loud as fawk! Trust me the first time you hear it open up you will swear you just went air born or your car blew up. :laugh: I definitly agree with the others. your mbc must not be hooked up right or improperly adjust. If your not hearing the o2 dump then your waste gate flapper isn't opening up. which means your boost is gonna go through the roof. If you have to take the mbc our and just connect a vac line the the wastegate actuator. you will run some real low boost then. good luck

 

[whitetiger777]

The boost controller is spliced into the line that goes from the throtle body to the blow off valve. The hoes that is T'ed into that line connectes with the brass nipple. The hose that goes to the aculator is attached to the blue nipple.

 

[RavenX]

am certain you have it hooked up wrong just wait until tonight when i get back from checking my car i'll let u know for sure

 

[oemdsm]

i havent installed my MBC yet until i fix my exhuast leak, so im running stock boost solenoid witch is 9 lbs for my 1g, but when i bypass my boost solenoid i still only run up to 9 lbs? why?

 

[onegee]

You run only 9psi because the stock wastegate spring is a 9psi spring.

 

[evolvingGS-t]

Try turning your boost down a notch the get on the car at WOT find out what it reads then. I have the same turbo on a 2g and I don't have spike issus, but on my EVO I had this problem because I had it set for 1.4bar and I got on it at WOT it would spike to 2.0bar.

 

[whitetiger777]

I'm acutaly trying to turn my boost down. I would love to see 0-5 psi, and them adjust up from there.

 

[TurboGarageTech]

I did however switch the hoes just to check and it jumped up to 22 psi fast

Here's your problem. You need to get a ho that doesn't blow so damn hard. Ouch.

 

[Bluebyu96Tsi]

take a vacumm line straight from your intake manifold, skip the turbo xs mbc and run the line straight to the wastegate accuator, then see if you turbo is still creeping as bad. If it doesn't creep as bad then you need to tune your MBC better. Just trying to help, good luck with it man.

 

[1fastlaser]

Ive seen alot of problems with those internal gates.I think its best to invest in a external of some kind

 

[silver eclipse]

Try doing what bluebyu says, your wastegate could be stuck closed and not opening to begin with, when i installed my 16g i think it was stuck closed, cuz with the turbo xs mbc all the way clockwise it would shoot up to 20 psi, very easy. But when i was trying to figure out why, ii drove it and heard a lil noise like a pop almost and the boost all the sudden droped down to 8 psi, (8 probly do the the fact no exhaust so it spikes and creeps anyways)

 

[whitetiger777]

Ok, I finaly found time to install a hose from my line directly to the aculator, bypassing the boost controller. I'm still reaching 20 or more psi. I also grabed the waste gate tab with a set of plyers and moved it. It moved, not a lot, but it was rather stiff. Could I not be getting enough pressure to open the waste gate?

 

[1fastlaser]

Ive seen alot of problems with those internal gates.I think its best to invest in a external of some kind

Like i said,try to get a external of some sort,eather a o2 housing setup or off the manifold