Welcome to the North American Subaru Impreza Owners Club Friday July 25, 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

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 05-08-2005, 12:30 PM   #1
BIGSKYWRX
Scooby Guru
 
Member#: 7958
Join Date: Jul 2001
Location: Plains of Eastern Montana
Vehicle:
09 GH B+

Default ECU reset-> 16 IAM = "aggressive" knock correction

I did a log w/ a oe ecu (3rd gear pull ~1800-redline) and found the IAM to stay right at 16, knock correction started in the 5ish range-> 9ish range @ ~3000 rpms-> to a high of a 10.5 @~ 4800 rpms -this is on a ECU that had not been reset in a couple of months.

I then put in my reflashed ECU (Ecutek), I advanced the IAM to 16 in matter of seconds (Shiv's "trick") and then immediately did another 3rd gear pull- the knock correction quickly advanced to 10 by ~ 2700 rpms, then dropped and hovered between 5 and 3 throughout the rest of the pull. The IAM stayed at 16 until ~ 3100 rpms and then started dropping- reaching a low of 6 @ ~3600 rpms and gaining one back to 7 @ ~ 4200.

Could this be a function of "fine learning"? Is knock correction more aggressive immediately following a reset?

If (I will ) repeat this in a couple of weeks of driving- is it possible (likely?) to see different results ie IAM remaing the same, knock correction "less aggressive"?

<----- knows suspensions pretty well, has long way to go w/ EM

Danka
* Registered users of the site do not see these ads.
BIGSKYWRX is offline   Reply With Quote
Old 05-08-2005, 11:08 PM   #2
Uncle Scotty
Scooby Guru
 
Member#: 16200
Join Date: Mar 2002
Vehicle:
OK Houston
we have an Uncle

Default

....try the same thing with 100 octane in the tank and see what happens
Uncle Scotty is offline   Reply With Quote
Old 05-08-2005, 11:17 PM   #3
BIGSKYWRX
Scooby Guru
 
Member#: 7958
Join Date: Jul 2001
Location: Plains of Eastern Montana
Vehicle:
09 GH B+

Default

I hear you, would be better even w/ 93

I have read a couple of threads that hint at the knock correction being a little "agressive" w/ a clean slate- I guess I'll find out.
BIGSKYWRX is offline   Reply With Quote
Old 05-08-2005, 11:20 PM   #4
thesmokingman
Scooby Specialist
 
Member#: 17751
Join Date: Apr 2002
Location: I want to believe...
Vehicle:
2002 WRX Wagon
944 Turbo track

Default

Quote:
Originally Posted by BIGSKYWRX
I have read a couple of threads that hint at the knock correction being a little "agressive" w/ a clean slate- I guess I'll find out.
Sounds plausible, especially given the OEM safey concerns.
thesmokingman is offline   Reply With Quote
Old 05-09-2005, 02:29 AM   #5
Uncle Scotty
Scooby Guru
 
Member#: 16200
Join Date: Mar 2002
Vehicle:
OK Houston
we have an Uncle

Default

Quote:
Originally Posted by BIGSKYWRX
I hear you, would be better even w/ 93

I have read a couple of threads that hint at the knock correction being a little "agressive" w/ a clean slate- I guess I'll find out.


....what I meant was that you could 'see' the difference and that would make it all the clearer to you.....
Uncle Scotty is offline   Reply With Quote
Old 05-09-2005, 08:38 AM   #6
mbiker97
Scooby Guru
 
Member#: 7922
Join Date: Jun 2001
Chapter/Region: MWSOC
Location: Tucson
Vehicle:
04 CTS-V b/b/b
99 GMC Highrider

Default

When my got my ECU reflashed my tuner put my IAM at 16 as the base number. It learned very quickly, and agressively.
mbiker97 is offline   Reply With Quote
Old 05-09-2005, 09:28 AM   #7
BIGSKYWRX
Scooby Guru
 
Member#: 7958
Join Date: Jul 2001
Location: Plains of Eastern Montana
Vehicle:
09 GH B+

Default

Here's a quote from Vaus in another thread "I've noticed that immediately after a reset, the ECU is "eager" to adjust the IAM based on any knock sensor feedback within the specified learning range. After driving the car for a while, however, the IAM becomes more or less static unless a lot of knock is detected. Once the IAM has settled, the fine ignition learning can adjust a good deal without effecting the IAM"

My thought is if true, then a map that has a "little time under it's belt" might easier to deal w/ ?

Scotty- I'm running crappy 91 pump gas- the best we are "blessed" w/- I would guess that w/ higher octane I would see less knock correction (w/ a corresponding less likelyhood of seeing a drop in IAM).
BIGSKYWRX is offline   Reply With Quote
Old 05-10-2005, 09:41 AM   #8
jblaine
Scooby Guru
 
Member#: 8512
Join Date: Jul 2001
Chapter/Region: South East
Location: St. Pete, FL
Vehicle:
2002 WRX chassis...
stage-infinity.com

Default

With higher octane, I'd expect you to see HIGHER "knock correction" (more timing).
jblaine is offline   Reply With Quote
Old 05-10-2005, 09:45 AM   #9
jblaine
Scooby Guru
 
Member#: 8512
Join Date: Jul 2001
Chapter/Region: South East
Location: St. Pete, FL
Vehicle:
2002 WRX chassis...
stage-infinity.com

Default

Quote:
Originally Posted by Vaus
I've noticed that immediately after a reset, the ECU is "eager" to adjust the IAM based on any knock sensor feedback within the specified learning range. After driving the car for a while, however, the IAM becomes more or less static unless a lot of knock is detected. Once the IAM has settled, the fine ignition learning can adjust a good deal without effecting the IAM
I don't know what Ed was basing this on, but it's pretty empty without data. IAM becomes more or less static-SEEMING because it has settled, IMO. Go fill up on 87 octane, without an ECU reset, and you'll see how quickly IAM drops.
jblaine is offline   Reply With Quote
Old 05-10-2005, 09:56 AM   #10
BIGSKYWRX
Scooby Guru
 
Member#: 7958
Join Date: Jul 2001
Location: Plains of Eastern Montana
Vehicle:
09 GH B+

Default

Quote:
Originally Posted by jblaine
With higher octane, I'd expect you to see HIGHER "knock correction" (more timing).
Correct- I mistated- meant a lower drop in correction.

If there is no difference in a ecu that is freshly reset and one that isn't- curious why deltadash "warns" you that you will lose all fine learning, etc.

What role does all of the fine learning play in the scheme of things?

Big Sky
BIGSKYWRX is offline   Reply With Quote
Old 05-10-2005, 10:05 AM   #11
jblaine
Scooby Guru
 
Member#: 8512
Join Date: Jul 2001
Chapter/Region: South East
Location: St. Pete, FL
Vehicle:
2002 WRX chassis...
stage-infinity.com

Default

It's nothing different than (in concept) long-term fuel trim.

Who knows why DD "warns" you. Just a notice that your car might run like ass for a few days and not to panic, I'd guess.
jblaine is offline   Reply With Quote
Old 05-10-2005, 10:12 AM   #12
BIGSKYWRX
Scooby Guru
 
Member#: 7958
Join Date: Jul 2001
Location: Plains of Eastern Montana
Vehicle:
09 GH B+

Default

The car does run better then (everything being equal- octane etc) after it has some "learning" under it's belt?

Is it possible knock correction is "learning" more eagerly w/ a reset vs a month w/o a reset?

Thanks
BIGSKYWRX is offline   Reply With Quote
Old 05-10-2005, 10:12 AM   #13
jblaine
Scooby Guru
 
Member#: 8512
Join Date: Jul 2001
Chapter/Region: South East
Location: St. Pete, FL
Vehicle:
2002 WRX chassis...
stage-infinity.com

Default

If you want more details, read these http://forums.nasioc.com/forums/show...3&page=1&pp=25

That's about the best info some of us were able to gather.
jblaine is offline   Reply With Quote
Old 05-10-2005, 10:18 AM   #14
BIGSKYWRX
Scooby Guru
 
Member#: 7958
Join Date: Jul 2001
Location: Plains of Eastern Montana
Vehicle:
09 GH B+

Default

Danka
BIGSKYWRX 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
How come I Can't see feedback knock correction, fine learning knock correction? AraSh Open Source Reflashes 23 01-08-2014 07:04 PM
negative knock correction but IAM @ 1 ? foresterated AccessPort 5 10-17-2008 11:37 AM
Correlations between Knock Lite and negative knock correction xFactor Engine Management & Tuning 1 01-12-2006 07:36 PM
RS ECU wow - Knock Correction Hitokiri Normally Aspirated with bolt-on Forced Induction Powertrain 1 08-08-2005 03:23 PM
IAM = 16, Knock Correction learning turns off. jblaine Engine Management & Tuning 41 09-12-2004 10:49 AM


All times are GMT -4. The time now is 04:41 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.