Turbo Boost Creep Creeping T25 14B 16G [Merged]

[csgsx23]

+1 for porting it out. Better safe than having to pull it apart again.

 

[DontStartModdin]

Thanks for the replys. Should I still port the exhaust hole on the wastegate and the o2 housing? And also what parts should be replaced when I have it all taken apart? Thnx

 

[96_charcoal_tsi]

I would at least port the turbo inlet and wastegate passage. Then port the o2 housing to match. Replace all the gaskets when you get it off. I had three inch turbo back exhaust and a ported 14b and didn't have any issue of creep. good luck

 

[99gst_racer]

Thanks for the replys. Should I still port the exhaust hole on the wastegate and the o2 housing? And also what parts should be replaced when I have it all taken apart? Thnx

Porting Guide

Porting the O2 housing is optional.

 

[El Cuervo]

You will creep with a 3inch on a 14b. Specially if you go catless.

 

[turbolover10]

I dont think its fuel cut,If it was fuel cut you would know it. Youd be checking in your rear view mirror to see if your trans is behind you or looking to see if you just tanked a large animal. Sputtering might be the plugs and/or wires. might be a clogged fuel filter as well

+1,
Sounds like a really bad boost leak to me.

When you say it goes up to 20psi and then drops down to 12, are you letting off or still going wot when it drops back down to 12psi cause if your still getting on it,its spike not creep.

 

[turboglenn]

Or boost spike! Mine had this problem on my 16g untill i ported teh internal gate out HUGE and fitted a larger flapper valve onto it. it wasn't easy, but i had more time than money and it fixed it to a point ( i would only spike a few PSI over my initial setting.. A larger laggy turbo fixed this for me permantly, but that's not an option for everyone....

I'm not sure of other remedies for spike, but i know it was a very common thing back when i was first building my dsm nearly 9 - 10 years ago.

 

[nfernotalon]

Hey everyone, all my mods are on my profile, but heres the story. I just adjusted my timing monday for the first time it was off by just a bit but it made a huge difference my car idles smoother and pulls harder, but now i have a dilemma i get boost creep to 20psi so far i get scared and have to let off the throttle..

I have my turbonetics MBC at the lowest, is it time to port my o2 housing already or get a ported one?? It didnt do this before i set my timing. Thanx everyone. somebody help

 

[boostnhard]

stock turbo? if it is, thats not cause by your exauhst being too small. i would check vaccum lines and do a leak down test

 

[nfernotalon]

stock turbo? if it is, thats not cause by your exauhst being too small. i would check vaccum lines and do a leak down test

Yep stock turbo and exhaust

 

[nfernotalon]

Ok here's the dilemma, I know why boost creep happens, either you put an aftermarket exhaust, bigger turbo etc... usually its your stock restrictive o2 housing that needs porting right? Ok so im getting boost creep to 20psi so far. I have to keep from going full throttle on the road because of that, I havent changed anything just set my timing right, it was off by a bit, thats all i did.

My turbonetics MBC is set all the way to the lowest point, stock turbo and exhaust, im about to order a new o2 housing from ebay.

 

[lAsErfWd]

I think that if the wastegate isnt opening, boost will keep rising or boost creep. First check for major exhaust leaks then check your wategate flapper door and make sure it is opening.

 

[nfernotalon]

I think that if the wastegate isnt opening, boost will keep rising or boost creep. First check for major exhaust leaks then check your wategate flapper door and make sure it is opening.

Id have have to take off the o2 housing to check the flapper right? Or is there another way?

 

[lAsErfWd]

Yes you would have to take the o2 housing off and then it is very easy to see on the turbine housing where the flapper door is. If it does not open then your actuator is probably bad.

 

[GS-T_Newboost]

check for any vacume leaks around the boost controler

 

[UKNOWHO]

if you get some pliers and grab the actuator arm you should be able to pull on it and it open a good inch or two you can try that test first to pinpoint your problem also boost creep is effected by the o2 housing but more so from the turbine housing. the wastegate hole is small and ###### needs some porting

 

[turbolover10]

+1 on the turbine housing.
Chances are replacing the 02 housing isn't going to help with creep, yes its restrictive but like said above the wastegate path in the turbine housing is the main problem.

First what turbo are you running and when did it start creeping? Have you tried bypassing you mbc yet?

Also if you want to test your w/g actuator and flapper you can boost leak test it and watch to see if it open like said above but without the pliers.

In most cases a perfect port job on the turbine housing and a nicely ported o2 housing will cure creep altogether.

 

[nfernotalon]

+1 on the turbine housing.
Chances are replacing the 02 housing isn't going to help with creep, yes its restrictive but like said above the wastegate path in the turbine housing is the main problem.

First what turbo are you running and when did it start creeping? Have you tried bypassing you mbc yet?

Also if you want to test your w/g actuator and flapper you can boost leak test it and watch to see if it open like said above but without the pliers.

In most cases a perfect port job on the turbine housing and a nicely ported o2 housing will cure creep altogether.

It started creeping bout a week ago when I adjusted my timing, didnt do anything but that, why would it start creeping after that? Also before my timing I would try tu turn it up to 15 psi but it would stay at 12 no matter how high i turned the MBC, now it creeps! (oh and i love the exhaust on your car HKS?)

 

[nhaspentr]

uhhh... make sure that the ball and spring assembly inside the MBC hasnt come apart. ive seen that happen and youll basically be running unlimited boost until you reset them.

sounds dumb i know... saw it with a Perrin MBC.

 

[nhaspentr]

It started creeping bout a week ago when I adjusted my timing, didnt do anything but that, why would it start creeping after that? Also before my timing I would try tu turn it up to 15 psi but it would stay at 12 no matter how high i turned the MBC, now it creeps! (oh and i love the exhaust on your car HKS?)

and it probably wouldnt go higher due to a boost restriction from the factory ECM. i know that some subies encountered this issue. a simple tune fixes it. g/l. hope i was some sort of help.

 

[synthetek]

Id have have to take off the o2 housing to check the flapper right? Or is there another way?

You can use a compressor to blow air into the line going to the actuator to see if it opens you could also disconnect the arm from the actuator to the flapper & see if the flapper moves freely.

 

[Kyle97turbo]

Ok to start out I put an evo3 turbo on my 97 gsx. Two months later I pulled it back off to fully port it and the 2g manifold. Got it all back together now and I still creep uncontrollably even with an open dump wastegate. I have been starting to wonder if a bad enough boost leak would cause boost creep. I have an hks ssqv bov and I can hear a leak where the vacuum line goes the the bov since the nipple on the hks is so much smaller. I'm getting incredibly sick of this thing creeping and am just about to go 50 trim and external and be done. Would anybody happen to have some insight on my situation??? Thank you very much for any help.

 

[absolute_DSM]

Fix the leak at your HKS first.

Hows your port job look? Obviously the exhaust is wanting to flow more through your turbine than the open wastegate, so some work may be needed there.

 

[Kyle97turbo]

Well the port job resembled a forced performance port job so that should be fine. I have been wondering if the 1.5" dump pipe is actually hindering exhaust flow rather than helping it flow.

 

[dsmdragon]

So have you ported the wastegate inlet and outlet port. making it easier for the gases to flow, will solve the problem. Polish both sides which will make the exhuast flow faster through the wastegate.... go to vfaq.com and go to porting and you can see what to do tot he exhuast housing