Welcome to the North American Subaru Impreza Owners Club Thursday July 19, 2018
Home Forums WikiNASIOC Products Store Modifications Upgrade Garage
Go Back   NASIOC > NASIOC Technical > Service & Maintenance

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.
* Registered users of the site do not see these ads. 
Thread Tools Display Modes
Old 09-24-2017, 03:22 AM   #1
Scooby Newbie
Member#: 404803
Join Date: Oct 2014
Default STI sputtering under load, no CEL

Hello Guy's/Gal's, I am currently dealing with a issue that has plagued my car for the past few months that I have been trying to diagnose by throwing parts at my car related to the problem.

-My problem: Car sputters when trying to get into boost at cruising speeds with more then 50% throttle.

during the event of the sputtering the smell of unburnt fuel becomes apparent. I have noticed looking back in my rear view mirror once during this sputtering event, I noticed what I would guess to be gas shooting out of the tailpipe accompanied by a plume of white-ish smoke.

-My Mods: nvidia catless bellmouth down pipe, Killerbee oil pickup, Tomei Turbo Inlet, accessport w/ COBB OTS ACN Stage 2 map

-Status report: The car currently has 177k on original factory motor/turbo. The clutch has a little over 3k miles. The car does consume oil at a rate that should cause for concern, but I don't notice smoke coming out of the oil fill tube with the cap off while reving the motor, nor do I experience smoke continuously billowing out of my exhaust. So based off of those symptoms I don't believe I have ringland failure or bad turbo seals. I had a compression test done about a year ago, and the shop that performed it told me I didn't have any compression loss, but then again.. that was a year ago.

-Maintenance performed/parts replaced: New Tomei silicone turbo inlet, New OEM spark plugs, New OEM coil packs, New OEM Injectors, New OEM MAF sensor, New OEM front and rear o2 sensors, New Walbro 255 LPH fuel pump /w new fuel filter included.

It's been a few years since a post related to this particular topic has be discussed, I'm hoping within those years others have had other luck with fixes to this problem other then those previously posted. Any help is greatly appreciated, thanks!
* Registered users of the site do not see these ads.
04stidaily is offline   Reply With Quote
Sponsored Links
* Registered users of the site do not see these ads.
Old 10-04-2017, 11:07 PM   #2
Scooby Newbie
Member#: 303367
Join Date: Dec 2011

Any chance you can get a OBD reader and Long term & Short term fueling ?
element91 is offline   Reply With Quote
Old 10-13-2017, 04:43 AM   #3
Scooby Newbie
Member#: 404803
Join Date: Oct 2014

Problem solved. Ended up being loose bolts that hold the hard lines to the TGV’s... I was about to replace my injector seal when I got to those two bolts, I realized they were loose. Me and a buddy of mine recently replaced a fuel hose that was leaking and we ended up taking the manifold off. I figure these were not torqued down when reassembly took place... all this time and money spent on replacing parts chasing this ended up being overlooked loose bolts.
04stidaily is offline   Reply With Quote

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 07:25 AM.

Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2018 Axivo Inc.
Copyright ©1999 - 2017, North American Subaru Impreza Owners Club, Inc.