Notices
Evo Engine / Turbo / Drivetrain Everything from engine management to the best clutch and flywheel.

boost sputters under WOT

Thread Tools
 
Search this Thread
 
Old Oct 15, 2013 | 02:18 PM
  #1  
1 evo8 1's Avatar
Thread Starter
Newbie
iTrader: (4)
 
Joined: Apr 2013
Posts: 35
Likes: 0
From: ankeny iowa
boost sputters under WOT

cant figure out what the problem is.. every time i boost it after like 10 psi a weird noise comes out the exhaust and i have major power loss..
i've tried it in every gear there all the same just sputters and goes no where.
put new plugs in gaped them to the right specs.. boost leak tested and just the throttle body seals are leaking. dont know if thats from it.
anyone else have a similar issue?
Reply
Old Oct 15, 2013 | 02:21 PM
  #2  
ThatOneKid's Avatar
Evolving Member
iTrader: (3)
 
Joined: Aug 2010
Posts: 278
Likes: 0
From: 9100' in the mountains of Colorado
I would say compressor surge but 10 psi seems way too low. Check your wastegate to make sure thats working right. Other guess would be a coil pack or the coil wire. What did you gap the plugs to?
Reply
Old Oct 15, 2013 | 02:25 PM
  #3  
1 evo8 1's Avatar
Thread Starter
Newbie
iTrader: (4)
 
Joined: Apr 2013
Posts: 35
Likes: 0
From: ankeny iowa
it depends tho.. last time i hit like 20 psi and right when i hit that the needle started going up and down and the noise came out agian. and .032. how can it be coil packs?
Reply
Old Oct 15, 2013 | 05:28 PM
  #4  
jayg4u's Avatar
Newbie
Veteran: Air Force
iTrader: (2)
 
Joined: Jan 2012
Posts: 29
Likes: 0
From: Boise ID
.32 is too large. Take it down to .24 or so
Reply
Old Oct 15, 2013 | 09:52 PM
  #5  
1 evo8 1's Avatar
Thread Starter
Newbie
iTrader: (4)
 
Joined: Apr 2013
Posts: 35
Likes: 0
From: ankeny iowa
would it make that big of a difference? with my old plugs it only did it first second and third, with new plugs it does it in all gears and idk if this is relevant but every time i boost it something smells gassy...
Reply
Old Oct 16, 2013 | 01:05 AM
  #6  
wang4u's Avatar
Evolving Member
iTrader: (3)
 
Joined: Apr 2013
Posts: 148
Likes: 4
From: Denver
Sounds like exhaust leak. Mine was starting to smell the same under high boost (in my case, smelt like unburnt fuel when the hvac was set on fresh air). Turns out the twinscroll gasket and downpipe gasket were leaking. They also cause some boost fluctuations. Only way to test it is to put your hand nearby the turbo. Otherwise youll need to take it all apart.

It could be injector leak but you would smell gas under the hood. I would check it first to rule them out but my guess is turbo gaskets. Good luck
Reply
Old Oct 16, 2013 | 02:40 AM
  #7  
MR. EVO MR's Avatar
Account Disabled
iTrader: (9)
 
Joined: Jan 2005
Posts: 1,761
Likes: 4
From: :noitacoL
Your plugs are gapped way way to high!!
Double check but I think its .20???

Last edited by MR. EVO MR; Oct 16, 2013 at 02:41 AM. Reason: Stupid spell check words lol
Reply
Old Oct 16, 2013 | 05:25 AM
  #8  
IEXCELR8's Avatar
Evolved Member
iTrader: (6)
 
Joined: Mar 2004
Posts: 1,034
Likes: 0
From: NJ
Do you have a cat on the car? what are you controlling boost with?

Here reply #22 has quite a few things for you to check. My guess is wastegate, and yes re-gap plugs to.024

https://www.evolutionm.net/forums/ev...an-12-psi.html
Reply
Old Oct 16, 2013 | 08:18 AM
  #9  
wang4u's Avatar
Evolving Member
iTrader: (3)
 
Joined: Apr 2013
Posts: 148
Likes: 4
From: Denver
Originally Posted by MR. EVO MR
Your plugs are gapped way way to high!!
Double check but I think its .20???
Stock is between .28 to .32. Its not the plugs. Though I do agree .24 to .27 is a better choice.
Reply
Old Oct 16, 2013 | 08:32 AM
  #10  
thedru13's Avatar
Evolved Member
iTrader: (24)
 
Joined: Sep 2008
Posts: 1,359
Likes: 5
From: West Chester PA
What are you using to control boost? MBC or EBC?
Reply
Old Oct 16, 2013 | 12:41 PM
  #11  
1 evo8 1's Avatar
Thread Starter
Newbie
iTrader: (4)
 
Joined: Apr 2013
Posts: 35
Likes: 0
From: ankeny iowa
mbc.. put your hand near the turbo? like feel if there air coming out or what?
Reply
Old Oct 16, 2013 | 02:09 PM
  #12  
ThatOneKid's Avatar
Evolving Member
iTrader: (3)
 
Joined: Aug 2010
Posts: 278
Likes: 0
From: 9100' in the mountains of Colorado
Originally Posted by 1 evo8 1
mbc.. put your hand near the turbo? like feel if there air coming out or what?
He's saying check if there's exhaust gas coming out where the manifold goes into the turbo, if I'm not mistaken.
Reply
Old Oct 16, 2013 | 03:36 PM
  #13  
llDemonll's Avatar
Evolved Member
iTrader: (21)
 
Joined: Jan 2011
Posts: 3,231
Likes: 99
From: Washington
re-gap your plugs to .022" and see if it fixes the issue. .032 is way too big
Reply
Old Oct 16, 2013 | 04:44 PM
  #14  
wang4u's Avatar
Evolving Member
iTrader: (3)
 
Joined: Apr 2013
Posts: 148
Likes: 4
From: Denver
Originally Posted by ThatOneKid
He's saying check if there's exhaust gas coming out where the manifold goes into the turbo, if I'm not mistaken.
Yep. If you smell gas or unburnt fuel it is definitely a leak in the exhaust. Do you smell it while the car is idling? Mine didnt, only when in boost. Any psi. Check for leaks with your hand. Or you could make up some soap and water in a spray bottle and spray it around where the turbo mates with the manifold. Ideally do it on a cold start.

Absolute worst case will be to take off the turbo assembly to check if the gaskets are bad. Before that do a boost leak test if you havent already.
Reply
Old Oct 16, 2013 | 06:36 PM
  #15  
1 evo8 1's Avatar
Thread Starter
Newbie
iTrader: (4)
 
Joined: Apr 2013
Posts: 35
Likes: 0
From: ankeny iowa
i've done a boost leak check and only the throttle body is leaking. and yea no matter what boost it smells.. sounds good i'll check that out tomorow
Reply



All times are GMT -7. The time now is 04:18 AM.