Welcome to the North American Subaru Impreza Owners Club Friday November 28, 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 11-16-2007, 09:40 PM   #1
hao
Scooby Newbie
 
Member#: 32026
Join Date: Jan 2003
Location: Bay Area, CA
Default 2.5L Motor Swap - HELP! Need ECU GURU

My buddy and I have been working on his 02 WRX for 9 months now, swapping in a 2.5L Legacy motor to run properly in his 02 WRX with stock ECU and wiring harness. All tuning I have done thus far has been with Enginuity software. We have tracked down several boost leaks, discovered we had bad injectors, removed the TGV, disabled the AVCS, and found various exhaust leaks and fuel pressure problems. All gremlins which have not fixed the real problem.

The car pulls great from idle to around 4500 rpm, and then around 4500 the car just falls flat on its face. Engine loads and boost just drop off. Now I realized we were probably maxing the MAF values so I rescaled the MAF values to coincide with the Legacy GT MAF values. We have tried to trouble shoot everything we could but the problem still does not go away. I'm beginning to think its a limitation on the 02 ECU which is giving us problems.

Has anyone else been successful at doing a 2.5L motor swap into an 02-03 and run the stock reflash ecu? Sample log below.

Car:
2002 WRX
2.5L Motor and Turbo from 2006 Legacy GT
Removed TGV valves
Disabled AVCS - STI Cams modified to run WRX Cam gears
ADJ Fuel Pressure Regulator
Fuel Rails to run Top Feed Injectors
Stock Injectors - only hitting 80% duty cycle
Walbro Fuel Pump
Headers, upipe, Turboback exhaust
Bigger TMIC

Log Files:
AFR EL RPM FP IAM TIMI Inj Dut Knock Air Pre MAF WG TPS
11.25 4.3 3924 100 14 4 61.15 4.5 15.96 142.25 42.35 100
11.25 4.33 4132 100 14 4.5 65.23 4.5 16.11 148.36 43.92 100
11.25 4.33 4266 100 14 4.5 68.26 4.5 16.25 154.76 43.92 100
11.25 4.33 4417 100 14 4.5 71.61 4.5 16.25 162.29 43.92 100
11.25 4.36 4646 100 14 13 46.36 3.5 9 101.49 43.92 100
11.25 2.69 4735 100 14 15.5 42.42 3.5 3.92 99.08 51.76 100
11.25 2.49 4838 100 14 16.5 42.32 3.5 3.05 96.94 67.45 100
11.25 2.42 4896 100 14 20 41.77 2.5 2.32 97.37 72.55 100
11.25 2.37 4970 100 14 21 41.35 2 2.03 96.51 72.55 100
11.25 2.32 5081 100 14 21.5 42.58 1.5 1.6 96.3 72.55 100
* Registered users of the site do not see these ads.

Last edited by hao; 11-16-2007 at 11:23 PM.
hao is offline   Reply With Quote
Old 11-17-2007, 12:42 AM   #2
hao
Scooby Newbie
 
Member#: 32026
Join Date: Jan 2003
Location: Bay Area, CA
Default

Post of Data Log

Code:
Air/Fuel Engine Load (2*g/rev)	Engine Speed (rpm) FI Pulse(ms)	Fuel Pump(%) IAM (IAM) Ignition(degrees) Injector(%) Knock(degrees) Manifold Relative Pressure (Corrected) (psi)	Mass Air Flow (g/s) Primary Wastegate Duty Cycle (%) Throttle Opening Angle (%)
11.37		2.82		3038		11.52		100		14		9		26.73		4.5		7.25		81.18		72.55		100
11.25		3.2		3301		13.57		100		14		6.5		34.34		4.5		10.59		104.57		72.55		100
11.25		3.83		3607		16.38		100		14		2.5		43.97		4.5		15.82		142.83		72.55		100
11.37		4.66		4010		19.97		100		14		3.5		60.7		4.5		18.14		151.84		69.8		100
11.48		4.55		4352		20.22		100		14		4.5		67.59		4.5		16.4		155.63		50.2		100
11.37		4.27		4678		19.2		100		14		5		69.64		4.5		15.38		139.12		42.75		100
11.71		2.98		4889		12.29		100		14		20		68.87		2.5		2.9		96.08		47.45		100
11.6		2.34		5064		9.98		100		14		22.5		40.68		2		1.31		95		60		100
11.6		2.24		5252		9.73		100		14		25		41.47		0		0.15		95.86		72.55		47.06
12.17		2.06		5078		8.7		66.67		14		11.5		38.09		0		-10.01		15.26		28.63		0
19.06		0.38		4164		0		100		14		13		0		4		4.64		112.34		0		66.27
11.25		3.2		3826		13.31		100		14		4.5		46.2		4.5		12.91		136.26		37.65		100
hao is offline   Reply With Quote
Old 11-17-2007, 01:06 AM   #3
Master2192
RIP 10/12/83 to 02/10/08
Scooby Specialist
 
Member#: 83254
Join Date: Mar 2005
Chapter/Region: NWIC
Location: Roy, Washington
Vehicle:
98 2.5 RS
04 WRX

Default

your engine load, boost, timing all make huge jumps between 4600 and 4800 rpm in that log. Please send me the map, master2192@hotmail.com
Master2192 is offline   Reply With Quote
Old 11-17-2007, 01:54 AM   #4
Master2192
RIP 10/12/83 to 02/10/08
Scooby Specialist
 
Member#: 83254
Join Date: Mar 2005
Chapter/Region: NWIC
Location: Roy, Washington
Vehicle:
98 2.5 RS
04 WRX

Default

After looking at the map and logs I do not think it is the ECU or the tune (though that huge timing jump at 6400 will not help you in the long run). It definitely looks like a mechanical issue, if I was going to guess I'd say the TGVs were snapping shut under load but you said you removed the TGVs.

I have tuned a 05 WRX with 2.5L swap, Element GT52 turbo and BigMAF intake with modded stock injectors and had almost no issues. so it isn't a limitation of the ECU. You need to consider things such as the inlet collapsing, TGVs snapping shut, things of that nature that would severly limit the engine's ability to breath.
Master2192 is offline   Reply With Quote
Old 11-17-2007, 02:00 AM   #5
hao
Scooby Newbie
 
Member#: 32026
Join Date: Jan 2003
Location: Bay Area, CA
Default

Thanks Master2192. I have reduced the timing quite bit to smooth things out and reduce knock. But that still doesn't explain the strange condition. I will take a look at the mechanical suggestion you mentioned. I will post any new findings.



Quote:
Originally Posted by Master2192 View Post
After looking at the map and logs I do not think it is the ECU or the tune (though that huge timing jump at 6400 will not help you in the long run). It definitely looks like a mechanical issue, if I was going to guess I'd say the TGVs were snapping shut under load but you said you removed the TGVs.

I have tuned a 05 WRX with 2.5L swap, Element GT52 turbo and BigMAF intake with modded stock injectors and had almost no issues. so it isn't a limitation of the ECU. You need to consider things such as the inlet collapsing, TGVs snapping shut, things of that nature that would severly limit the engine's ability to breath.
hao is offline   Reply With Quote
Old 11-18-2007, 02:00 AM   #6
Smoby
Scooby Specialist
 
Member#: 97642
Join Date: Oct 2005
Chapter/Region: SWIC
Location: Phoenix, AZ
Vehicle:
2002 Wrx Sedan
MBP

Default

Your boost drops 13 psi within 200 rpm while you are full throttle.

Do you have an aftermarket blowoff? Is the stock one leaking? Do you have a silicon turbo inlet?
Smoby is offline   Reply With Quote
Old 11-18-2007, 03:31 AM   #7
hao
Scooby Newbie
 
Member#: 32026
Join Date: Jan 2003
Location: Bay Area, CA
Default

The car is running the stock BOV and we recently replaced the gasket as we discovered a leak a few weeks ago. The car does have the cheapy silicon turbo inlet pipe, which we be replaced next week. From what other people have told me, the non-reinforced silicon inlet pipe has a tendency to collapse.

I will keep everyone updated after we switch out the pipe. Thanks for all the input.


Quote:
Originally Posted by Smoby View Post
Your boost drops 13 psi within 200 rpm while you are full throttle.

Do you have an aftermarket blowoff? Is the stock one leaking? Do you have a silicon turbo inlet?
hao is offline   Reply With Quote
Old 11-21-2007, 09:25 PM   #8
hao
Scooby Newbie
 
Member#: 32026
Join Date: Jan 2003
Location: Bay Area, CA
Default

So I wanted to follow up and let everyone know we fixed the problem. It turns out the silicon turbo inlet hose was causing all the problems. The dreaded silicon hose was collapsing under full boost and would act as a restriction. We reinstalled the factory inlet hose and the car pulls great now.

Thanks to all who help me diagnose the problem.
hao 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
Cobb AccessPORT 2.0 for the 2.5L motors Robson TXIC Private Classifieds 3 02-24-2009 01:00 PM
2.2L-2.5L na swap help needed ASAP!!!!!! impreza4show Subaru Conversions 14 08-20-2005 03:58 AM
miata motor swap day...need help Blindeye_03 South East Region Forum 43 04-28-2005 06:56 PM
do 1.8, 2.0, 2.2, and 2.5L cams swap? JonofScio Normally Aspirated Powertrain 1 07-11-2004 10:00 PM
NY/NJ: Partial turbo kit for 2.2/2.5L motors Paisan Private 'For Sale' Classifieds 5 04-29-2004 11:58 PM


All times are GMT -4. The time now is 12:21 PM.


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.