Welcome to the North American Subaru Impreza Owners Club Tuesday March 2, 2021
Home Forums Images WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Go Back   NASIOC > NASIOC Technical > Factory 2.5L Turbo Powertrain (EJ Series Factory 2.5L Turbo)

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.







* As an Amazon Associate I earn from qualifying purchases. 
* Registered users of the site do not see these ads. 
Reply
 
Thread Tools Display Modes
Old 11-17-2020, 02:20 PM   #1
tomsti03
Scooby Newbie
 
Member#: 511743
Join Date: Feb 2020
Default Impreza Sti 2003 lost power hlgh rpm

Hi. I have European sti 2003 ej207 stage 2 340hp, as it turns out that one day it stopped blowing at high revs.
The car makes a small sound and the turbo pressure drops suddenly, going from 22psi to about 14 or less from an estimated 5200 rpm.

It is as if the engine does not suck or evacuate gases. I have changed the speed connector, coils, spark plugs, new gasoline pump, filter, checked the timing, I installed a fixed turbo wastegate, cleaned all the connections ...

It emits as a small blow and the turbo pressure drops suddenly, when before it reached 22 psi at cutoff. Turbo looks good

What do you think it may be?
* Registered users of the site do not see these ads.
tomsti03 is offline   Reply With Quote
Sponsored Links
* Registered users of the site do not see these ads.
Old 11-18-2020, 08:30 PM   #2
Scooby South
Subtly Outspoken
Moderator
 
Member#: 238
Join Date: Sep 1999
Chapter/Region: MWSOC
Vehicle:
OG05 STi
51E

Default

my first guess would be the Tune...the ECU controls the Boost controller and WILL cut if it reaches a certain level..
What are you using for Engine Management??
and What Turbo??? VF30-?? VF-22??
The other thing would be to check the wastegate actuator??? to see if its holding..
My guess is...its not holding the boost level you have designated for your Tune...

Someone else can chime in.. but those are my initial Thoughts..Good luck

Bill
Scooby South is online now   Reply With Quote
Old 11-18-2020, 09:18 PM   #3
Blackfin
Scooby Specialist
 
Member#: 361325
Join Date: Jul 2013
Chapter/Region: E. Canada
Location: Ontario
Vehicle:
2010 STi
Dark Gray Metallic

Default

Does the car still have a catalytic converter(s)? If so it may be damaged and causing a blockage.
Blackfin is offline   Reply With Quote
Old 11-18-2020, 10:22 PM   #4
Scooby South
Subtly Outspoken
Moderator
 
Member#: 238
Join Date: Sep 1999
Chapter/Region: MWSOC
Vehicle:
OG05 STi
51E

Default

Quote:
Originally Posted by Blackfin View Post
Does the car still have a catalytic converter(s)? If so it may be damaged and causing a blockage.
Good call.. That definitely is a possibility..

Bill
Scooby South is online now   Reply With Quote
Old 01-09-2021, 09:55 AM   #5
tomsti03
Scooby Newbie
 
Member#: 511743
Join Date: Feb 2020
Default Log inside

https://drive.google.com/file/d/1Y7v...ew?usp=sharing

Here's the log of the car. The car losses turbo pressure after 5000 rpm. The maf signal also drops and when this happens i hear a small hit sound.


I checked the syncronitation timing belt, changed the coil packs and spark plugs and no intake leaks.


The car was working fine and this happened suddenly, it has a fbo performance stage 2. Full exhaust 3", bov, walbro 340 classic stage 2.
tomsti03 is offline   Reply With Quote
Old 01-09-2021, 12:36 PM   #6
kopele
Scooby Newbie
 
Member#: 363007
Join Date: Jul 2013
Chapter/Region: MWSOC
Location: MO
Vehicle:
2008 STI
Black

Default

Not sure what the sound might be, but I would check the boost controller, wastegate, and vacuum lines. Looks like it might be dropping to spring pressure, which most often is around 14psi.
kopele is online now   Reply With Quote
Old 01-09-2021, 05:28 PM   #7
Gucciflipflops
Scooby Newbie
 
Member#: 521349
Join Date: Dec 2020
Chapter/Region: South East
Vehicle:
2005 Impreza WRX

Default

Possibly an exhaust issue. I think Steve Tuned on youtube had an issue similar to this and it ended up being something random in the exhaust system. If you have cats your cats could be going bad.
Gucciflipflops is offline   Reply With Quote
Old 01-10-2021, 02:52 PM   #8
tomsti03
Scooby Newbie
 
Member#: 511743
Join Date: Feb 2020
Default

Quote:
Originally Posted by kopele View Post
Not sure what the sound might be, but I would check the boost controller, wastegate, and vacuum lines. Looks like it might be dropping to spring pressure, which most often is around 14psi.
Already discard all that, lock wastegate mechanically to see that it does the pressure and does exactly the same.

Regarding the exhaust system, I do not have catalysts. I have a complete line 3 "plus kakumei collectors.
tomsti03 is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

All times are GMT -4. The time now is 11:07 PM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2021, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2021 Axivo Inc.
Copyright ©1999 - 2019, North American Subaru Impreza Owners Club, Inc.

As an Amazon Associate I earn from qualifying purchases.