Welcome to the North American Subaru Impreza Owners Club Tuesday September 23, 2014
Home Forums WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Here you can view your subscribed threads, work with private messages and edit your profile and preferences Home Registration is free! Visit the NASIOC Store NASIOC Rules Search Find other members Frequently Asked Questions Calendar Archive NASIOC Upgrade Garage Logout
Go Back   NASIOC > NASIOC Technical > Engine Management & Tuning > Commercial ECU Reflashes

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.
Reply
 
Thread Tools Display Modes
Old 11-22-2007, 03:09 PM   #1
drkramm
Scooby Specialist
 
Member#: 159156
Join Date: Sep 2007
Chapter/Region: Tri-State
Location: catasauqua, pa
Vehicle:
2007 wrx
wrb

Default boost cut 4th-5th gear

io was helping a friend tune his 06 wrx with a cbe and i was giving it a lil more boost and we had no proplems maxed at 15 psi ran great thru 3rd didn't pull any timing now today he was out and called me saying he had a cel but car was running fine and boosted fine so i reset the computor take it out 1,2,3 no proplems but 4th and 5th gear both will cause fuel cut around 3500-4000 rpms (around max boost)

rpm boost(psi wot)
800 3.52
1200 7.54
1600 8.16
2000 10.60
2400 13.92
3300 14.97
3600 13.77
4400 13.05
5600 12.10
6000 10.56
6400 9.86

the boost limit fuel cut is set at 16.07psi

am i jsut trying to run too much boost with the factory dp or should i nudge the fuel cut up a lil


i could't get the code scanned since its thanksgiving and most places are closed around here
* Registered users of the site do not see these ads.
drkramm is offline   Reply With Quote
Old 11-22-2007, 03:30 PM   #2
LateApex31
Scooby Newbie
 
Member#: 135686
Join Date: Dec 2006
Chapter/Region: NESIC
Location: six- one-seven
Default

The rate of change of RPM is slower in the higher gears which will cause this to happen. You need to balance the need for quick spoolup and meeting boost targets in the lower gears with controlling boost in the higher gears.
LateApex31 is offline   Reply With Quote
Old 11-22-2007, 03:32 PM   #3
drkramm
Scooby Specialist
 
Member#: 159156
Join Date: Sep 2007
Chapter/Region: Tri-State
Location: catasauqua, pa
Vehicle:
2007 wrx
wrb

Default

i understand what you mean but how do i go about doing it ?
thanks for the quick reply though
drkramm is offline   Reply With Quote
Old 11-22-2007, 03:42 PM   #4
drkramm
Scooby Specialist
 
Member#: 159156
Join Date: Sep 2007
Chapter/Region: Tri-State
Location: catasauqua, pa
Vehicle:
2007 wrx
wrb

Default

i think im jsut gonna back the boost off ran great at 13psi in all the gears
i doubt the extra 2 psi is really making that big of a diffrence specaily when its cutting out anyway
drkramm is offline   Reply With Quote
Old 11-27-2007, 04:16 PM   #5
bboy
Scooby Specialist
 
Member#: 56468
Join Date: Mar 2004
Chapter/Region: NWIC
Location: Seattle, WA
Vehicle:
04 Improved STI
Dirty White

Default

Are you running a MBC? They are more sensitive to both temperature and load. I'd only turn the boost cut up if you are not detonating.
bboy is offline   Reply With Quote
Old 11-27-2007, 06:40 PM   #6
drkramm
Scooby Specialist
 
Member#: 159156
Join Date: Sep 2007
Chapter/Region: Tri-State
Location: catasauqua, pa
Vehicle:
2007 wrx
wrb

Default

na its the factory bcs
drkramm is offline   Reply With Quote
Old 11-28-2007, 12:11 PM   #7
controler
Scooby Newbie
 
Member#: 100271
Join Date: Nov 2005
Chapter/Region: South East
Default

Are you hitting higher boost than in your targets? It could be an issue with the wastegate arm is too tight.
controler is offline   Reply With Quote
Old 11-28-2007, 12:57 PM   #8
bboy
Scooby Specialist
 
Member#: 56468
Join Date: Mar 2004
Chapter/Region: NWIC
Location: Seattle, WA
Vehicle:
04 Improved STI
Dirty White

Default

Maybe it's not "boost" cut. There are several fuel cuts that it could be. MAFv, Load, Boost,....

Try posting a log of: AFR, MAFv, Load, MRP, and RPM (you could throw knock correction, and AF learning and AF correction in there too if you want). Use the "code" wrapper to post the log.
bboy 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

Similar Threads
Thread Thread Starter Forum Replies Last Post
Wastegate opens 4th+5th gear low boost? 99subi Factory 2.0L Turbo Powertrain 5 03-18-2008 09:28 PM
04 sti 4th-5th gear grind? stiman17 Transmission (AT/MT) & Driveline 3 09-19-2007 05:32 PM
Weird 4th,5th gear problem fluxcapacitor Factory 2.0L Turbo Powertrain 5 07-30-2006 01:22 PM
Power loss @ 4th 5th gear......??? |los| Factory 2.0L Turbo Powertrain 11 01-31-2006 05:02 PM
4th - 5th gear grind kettsupp Warranty Issues & SOA Problems 5 10-19-2005 07:35 PM


All times are GMT -4. The time now is 12:56 AM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2014 Axivo Inc.
Copyright ©1999 - 2014, North American Subaru Impreza Owners Club, Inc.