Welcome to the North American Subaru Impreza Owners Club Monday July 6, 2015
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 > AccessPort

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 09-02-2013, 12:28 AM   #1
sebi1990
Scooby Newbie
 
Member#: 362910
Join Date: Jul 2013
Chapter/Region: MWSOC
Location: Chicago
Vehicle:
2013 Impreza WRX
White

Default 2013 wrx stage 1 feedback knock?!

Hey guys I've installed Cobbs OTS map for 93 with intake and my DAM is great always 1 however for a split second my feedback knock went from 0 to -1.4. I am still to log my data and post it but I wanted to find out if it s something that required imidiate attention. Also it happens at no paricular time or in a given gear. Also it happens very rearly.


Send from my android so the spelling is crap sorry ; (
* Registered users of the site do not see these ads.
sebi1990 is offline   Reply With Quote
Sponsored Links
* Registered users of the site do not see these ads.
Old 09-02-2013, 01:48 AM   #2
Chicago AJ
Scooby Specialist
 
Member#: 353343
Join Date: Apr 2013
Chapter/Region: MWSOC
Location: Suburb of Chicago
Vehicle:
'13 WRX Sedan Stg 3
'13 Prius C 86mpg!

Default

It's probably fine. Get some logs posted so we can take a look. Find a spot and log 2500rpm to redline at full throttle.
Chicago AJ is offline   Reply With Quote
Old 09-02-2013, 01:55 AM   #3
sebi1990
Scooby Newbie
 
Member#: 362910
Join Date: Jul 2013
Chapter/Region: MWSOC
Location: Chicago
Vehicle:
2013 Impreza WRX
White

Default

Since its a 5speed in 3rd gear right?
sebi1990 is offline   Reply With Quote
Old 09-02-2013, 02:18 AM   #4
Chicago AJ
Scooby Specialist
 
Member#: 353343
Join Date: Apr 2013
Chapter/Region: MWSOC
Location: Suburb of Chicago
Vehicle:
'13 WRX Sedan Stg 3
'13 Prius C 86mpg!

Default

Correct.
Chicago AJ is offline   Reply With Quote
Old 09-02-2013, 02:46 AM   #5
sebi1990
Scooby Newbie
 
Member#: 362910
Join Date: Jul 2013
Chapter/Region: MWSOC
Location: Chicago
Vehicle:
2013 Impreza WRX
White

Default

Awsome will post logs tomorrow if I'm able to :-)
sebi1990 is offline   Reply With Quote
Old 09-03-2013, 12:41 AM   #6
sebi1990
Scooby Newbie
 
Member#: 362910
Join Date: Jul 2013
Chapter/Region: MWSOC
Location: Chicago
Vehicle:
2013 Impreza WRX
White

Default


Last edited by sebi1990; 09-03-2013 at 12:50 AM.
sebi1990 is offline   Reply With Quote
Old 09-03-2013, 09:54 AM   #7
Cobb Tuning
NASIOC Vendor
 
Member#: 4803
Join Date: Mar 2001
Location: Austin, DFW, Portland, SOCAL
Default

Quote:
Originally Posted by sebi1990 View Post
A little bit of fine knock learning in this log but within tolerances and based on a previous event (has started to learn back to zero). Get a few more logs to verify (if you can do so safely) but looks fine.

Bill
Cobb Tuning is offline   Reply With Quote
Old 09-03-2013, 10:16 AM   #8
sebi1990
Scooby Newbie
 
Member#: 362910
Join Date: Jul 2013
Chapter/Region: MWSOC
Location: Chicago
Vehicle:
2013 Impreza WRX
White

Default

Quote:
Originally Posted by Cobb Tuning View Post
A little bit of fine knock learning in this log but within tolerances and based on a previous event (has started to learn back to zero). Get a few more logs to verify (if you can do so safely) but looks fine.

Bill
Great I will get 3 logs one after another hopefully today I don't know if it makes a difference but the logs were done after 2h of highway cruising is there any other data I should log in order to help you get better idea of what's happening with the engine? Also this is the first time the car got that sort of a beating.
sebi1990 is offline   Reply With Quote
Old 09-03-2013, 11:24 AM   #9
Cobb Tuning
NASIOC Vendor
 
Member#: 4803
Join Date: Mar 2001
Location: Austin, DFW, Portland, SOCAL
Default

Quote:
Originally Posted by sebi1990 View Post
Great I will get 3 logs one after another hopefully today I don't know if it makes a difference but the logs were done after 2h of highway cruising is there any other data I should log in order to help you get better idea of what's happening with the engine? Also this is the first time the car got that sort of a beating.
The default logging set is fine. Your log looks fine but it is always a good idea to get multiple logs to compare. The occasional small knock correction is perfectly fine and sometimes it is just noise and not actual knock.

Bill
Cobb Tuning is offline   Reply With Quote
Old 09-03-2013, 03:49 PM   #10
sebi1990
Scooby Newbie
 
Member#: 362910
Join Date: Jul 2013
Chapter/Region: MWSOC
Location: Chicago
Vehicle:
2013 Impreza WRX
White

Default

Hey I've got two more logs but they're just me coming from school a bit of spirited driving in 1st 2nd and 3rd at one point the know was above 2 here are the logs:

https://docs.google.com/file/d/0B1mT...VVJYW5vc3BPVmM

https://docs.google.com/file/d/0B1mT...3VrWEk1SDM0X28

I will post more logs hopefully today in the evening.
sebi1990 is offline   Reply With Quote
Old 09-03-2013, 03:49 PM   #11
sebi1990
Scooby Newbie
 
Member#: 362910
Join Date: Jul 2013
Chapter/Region: MWSOC
Location: Chicago
Vehicle:
2013 Impreza WRX
White

Default

Quote:
Originally Posted by Cobb Tuning View Post
The default logging set is fine. Your log looks fine but it is always a good idea to get multiple logs to compare. The occasional small knock correction is perfectly fine and sometimes it is just noise and not actual knock.

Bill
I heard a lot of people talk about the noise what is the noise exactly and how is it connected to knock and can appear to be a knock?
sebi1990 is offline   Reply With Quote
Old 09-03-2013, 04:12 PM   #12
Chicago AJ
Scooby Specialist
 
Member#: 353343
Join Date: Apr 2013
Chapter/Region: MWSOC
Location: Suburb of Chicago
Vehicle:
'13 WRX Sedan Stg 3
'13 Prius C 86mpg!

Default

Could something loose in the engine bay. A bolt, heatshield, etc. Driving under normal conditions the noise could be picked up by the knock sensor. Like Bill said, under hard load/full acceleration the engine is making much more noise and it could make the knock sensor not pick up the false knock.
Chicago AJ is offline   Reply With Quote
Old 09-03-2013, 04:28 PM   #13
sebi1990
Scooby Newbie
 
Member#: 362910
Join Date: Jul 2013
Chapter/Region: MWSOC
Location: Chicago
Vehicle:
2013 Impreza WRX
White

Default

Quote:
Originally Posted by Chicago AJ View Post
Could something loose in the engine bay. A bolt, heatshield, etc. Driving under normal conditions the noise could be picked up by the knock sensor. Like Bill said, under hard load/full acceleration the engine is making much more noise and it could make the knock sensor not pick up the false knock.
Ok thanks for the clarification.
sebi1990 is offline   Reply With Quote
Old 09-03-2013, 06:14 PM   #14
sebi1990
Scooby Newbie
 
Member#: 362910
Join Date: Jul 2013
Chapter/Region: MWSOC
Location: Chicago
Vehicle:
2013 Impreza WRX
White

Default

Also in 1st gear it seems as soon as I get off the throttle to switch gears the knock goes to 2.8
sebi1990 is offline   Reply With Quote
Old 09-03-2013, 07:05 PM   #15
Chicago AJ
Scooby Specialist
 
Member#: 353343
Join Date: Apr 2013
Chapter/Region: MWSOC
Location: Suburb of Chicago
Vehicle:
'13 WRX Sedan Stg 3
'13 Prius C 86mpg!

Default

Could be something loose or the driveline clunking.
Chicago AJ is offline   Reply With Quote
Old 09-03-2013, 07:53 PM   #16
bluemax189
Scooby Specialist
 
Member#: 137405
Join Date: Jan 2007
Chapter/Region: MAIC
Location: Baltimore
Vehicle:
2011 WRX
20g

Default

on a side note, boost seems to be a little off in the first log you posted. looks like you're running almost 2psi short until the upper rpm's. if you're comfortable tuning you could try and adjust the wgdc tables a bit.
bluemax189 is online now   Reply With Quote
Old 09-03-2013, 10:08 PM   #17
sebi1990
Scooby Newbie
 
Member#: 362910
Join Date: Jul 2013
Chapter/Region: MWSOC
Location: Chicago
Vehicle:
2013 Impreza WRX
White

Default

It seems like every time I step on it harder and then release the throttle to switch gears that happens. It hit -2.8 at times and it starts to worry me.
sebi1990 is offline   Reply With Quote
Old 09-04-2013, 08:29 AM   #18
Cobb Tuning
NASIOC Vendor
 
Member#: 4803
Join Date: Mar 2001
Location: Austin, DFW, Portland, SOCAL
Default

Quote:
Originally Posted by sebi1990 View Post
It seems like every time I step on it harder and then release the throttle to switch gears that happens. It hit -2.8 at times and it starts to worry me.
I wouldn't worry about feedback knock that occurs on hard shifts or when mashing the throttle or lifting abruptly off the throttle and long as it is not worse than -2.8. This is almost always noise. The -2.8 fine knock learning in the logs you are seeing is just based on a past event at lower load which is being re-applied over and over again (not current knock) as you pass through the load/rpm range which you were briefly hitting multiple times in these particular data logs.

The best logs to get to see how things are doing is like the first log you did - an extended 3rd gear WOT run, if you can do so safely.

Bill

Last edited by Cobb Tuning; 09-04-2013 at 08:44 AM.
Cobb Tuning is offline   Reply With Quote
Old 09-04-2013, 12:51 PM   #19
SouthernWRX
Scooby Newbie
 
Member#: 321571
Join Date: May 2012
Chapter/Region: TXIC
Location: Cypress, TX
Vehicle:
2012 WRX Base
Ice Silver

Default

My '12 WRX has never, NEVER been knock/knock learning free. It always has some here and there. Like Bill said, get another 3rd gear pull and see what its doing. Your going to drive yourself crazy cruising around always looking at the knock, I know I did. Trust me, if something is truly wrong you will know it. I got a tank of bad gas about a month ago and holy hell did it pull some crazy stuff on my car. Knock all the time, DAM down to .35. Once I finished that tank, everything has been back to normal. Get a 3rd gear WOT run and post it back up. That first log looked good, the other two are random driving and look about like mine at times.

Just so you know I went stage one at about 5K miles, then stage two at about 15K and I currently have 26K on her with no issues.
SouthernWRX is offline   Reply With Quote
Old 09-04-2013, 12:58 PM   #20
sebi1990
Scooby Newbie
 
Member#: 362910
Join Date: Jul 2013
Chapter/Region: MWSOC
Location: Chicago
Vehicle:
2013 Impreza WRX
White

Default

Quote:
Originally Posted by SouthernWRX View Post
My '12 WRX has never, NEVER been knock/knock learning free. It always has some here and there. Like Bill said, get another 3rd gear pull and see what its doing. Your going to drive yourself crazy cruising around always looking at the knock, I know I did. Trust me, if something is truly wrong you will know it. I got a tank of bad gas about a month ago and holy hell did it pull some crazy stuff on my car. Knock all the time, DAM down to .35. Once I finished that tank, everything has been back to normal. Get a 3rd gear WOT run and post it back up. That first log looked good, the other two are random driving and look about like mine at times.

Just so you know I went stage one at about 5K miles, then stage two at about 15K and I currently have 26K on her with no issues.

Yeah I've been doing that thanks for the reassurance guys I'll get the two pulls as soon as I can
sebi1990 is offline   Reply With Quote
Old 09-06-2013, 08:21 PM   #21
sebi1990
Scooby Newbie
 
Member#: 362910
Join Date: Jul 2013
Chapter/Region: MWSOC
Location: Chicago
Vehicle:
2013 Impreza WRX
White

Default

Hey guys I'm back with more data the

1st one was done on a bit bumpy road/ costco gas /traction control on:

https://docs.google.com/file/d/0B1mT...it?usp=sharing

2nd one was done on a smoother road / shell v-power / traction control off:

https://docs.google.com/file/d/0B1mT...it?usp=sharing


The knock is definitely lower in the 2nd one not sure if because of the gas or maybe the road condition.
sebi1990 is offline   Reply With Quote
Old 09-06-2013, 09:13 PM   #22
Chicago AJ
Scooby Specialist
 
Member#: 353343
Join Date: Apr 2013
Chapter/Region: MWSOC
Location: Suburb of Chicago
Vehicle:
'13 WRX Sedan Stg 3
'13 Prius C 86mpg!

Default

I'll check them when I get home in a couple hours. I always use Costco gas and have never seen any knock. Bill said my logs were good if you want to compare, check my newest thread with the A/B/C/D logs.
Chicago AJ is offline   Reply With Quote
Old 09-06-2013, 09:21 PM   #23
sebi1990
Scooby Newbie
 
Member#: 362910
Join Date: Jul 2013
Chapter/Region: MWSOC
Location: Chicago
Vehicle:
2013 Impreza WRX
White

Default

You are running stage 1 with or without intake?
sebi1990 is offline   Reply With Quote
Old 09-06-2013, 09:39 PM   #24
Chicago AJ
Scooby Specialist
 
Member#: 353343
Join Date: Apr 2013
Chapter/Region: MWSOC
Location: Suburb of Chicago
Vehicle:
'13 WRX Sedan Stg 3
'13 Prius C 86mpg!

Default

Without. The only thing that should change is boost.
Chicago AJ is offline   Reply With Quote
Old 09-07-2013, 09:15 AM   #25
Cobb Tuning
NASIOC Vendor
 
Member#: 4803
Join Date: Mar 2001
Location: Austin, DFW, Portland, SOCAL
Default

Quote:
Originally Posted by sebi1990 View Post
Hey guys I'm back with more data the

1st one was done on a bit bumpy road/ costco gas /traction control on:

https://docs.google.com/file/d/0B1mT...it?usp=sharing

2nd one was done on a smoother road / shell v-power / traction control off:

https://docs.google.com/file/d/0B1mT...it?usp=sharing


The knock is definitely lower in the 2nd one not sure if because of the gas or maybe the road condition.
The logs look good. There is a single count (-1.4) of fine knock learning in the first log that is ramping back to zero in that log and the next. Fine knock learning is a little tricky to analyze as it can happen from a prior event and is re-applied over and over in a load/rpm range surrounding event, so it is hard to tell when it was learned (sometimes you can get this correction at WOT when lifting off the throttle abruptly at the end of a WOT run which is just noise). I would get a few more of the same type of logs just to see additional data, if you can do so safely, but a single count of occasional fine knock learning is not a big deal.

We usually recommend the so-called "top tier" gas, which usually has more consistent results. We've seen issues with Costco gas before, but that is hard to apply universally as likely Costco gets gas from a wide variety of suppliers at different Costco throughout the country, so results may vary.

Bill
Cobb Tuning 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 11:17 AM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2015, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2015 Axivo Inc.
Copyright ©1999 - 2015, North American Subaru Impreza Owners Club, Inc.