Welcome to the North American Subaru Impreza Owners Club Thursday March 28, 2024
Home Forums Images WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Go Back   NASIOC > NASIOC Technical > Factory 2.0L Turbo Powertrain (EJ Series Factory 2.0L Turbo)

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.







* As an Amazon Associate I earn from qualifying purchases. 
* Registered users of the site do not see these ads. 
Reply
 
Thread Tools Display Modes
Old 11-11-2022, 05:47 PM   #1
nathanbunge
Scooby Newbie
 
Member#: 530551
Join Date: Jun 2022
Default 2002 WRX Knock?!?!? D:

Noticed my DAM decreased to 13 the other day, so I started doing some data monitoring. The last run I stayed out of boost, and my Feedback Knock hit just over 4 at around 350 seconds. Am I done for? Do I need a new engine?!?!

But for real, does anyone have any insight on what could be going on/what I could do to help this?

Datalog links:

-When DAM first decreased (on pull) : https://drive.google.com/file/d/1pRU...ew?usp=sharing
-light driving after DAM decreased: https://drive.google.com/file/d/1PWR...ew?usp=sharing

Car:
-2002 WRX Wagon
-160k miles
-Cobb OTS Stage 2+ 91 v350 tune. (I always put either 92 or 93 Octane in)

Mods:
-Cobb catted dp
-Catless Uppipe
-Cobb 3-port EBCS
-STI hood scoop and splitter

Recent Maintenance in last year:
-PCV valve
-Timing belt
-Spark plugs
-MAF sensor
-A/F Sensor (front o2 sensor)
* Registered users of the site do not see these ads.

Last edited by nathanbunge; 11-11-2022 at 06:00 PM.
nathanbunge is offline   Reply With Quote
Sponsored Links
* Registered users of the site do not see these ads.
Old 11-19-2022, 12:08 PM   #2
PSolbergfan
Scooby Specialist
 
Member#: 112612
Join Date: Apr 2006
Chapter/Region: MWSOC
Location: Appleton,Wisconsin
Vehicle:
2010 Legacy 2.5 CBS
2002 Impreza WRX WRB

Default

When I had my hybrid tuned years ago I had a new Denso MAF installed on the car. My tuner was having issues with tuning so he took a known good O.E.M. MAF out of one of his cars and the tune went much better. So he replaced the Denso MAF with a new O.E.M. MAF (Yes, I know the Subaru MAF is made by Denso) and life is good. I see you changed your MAF and AF sensor within the last year. Those are two critical sensors. Did you go with good, Denso sensors or O.E.M.? I would NOT trust anything else.

1. You may have gotten a bad tank of fuel.
2. Buy 5 gallons of racing fuel and mix it with the highest octane pump fuel you can buy. E10 is okay. See if your problem still exists. This will determine if you have a tuning/ mechanical issue or just a bad tank of fuel.
3.Did you do a ECM reset? That may help.
4.Does your DP have an accommodation for another A/F/ sensor? If so, install one. A.E.M. makes a good kit with gauge. It's redundant but you'll be able to see if the sensor feeding the ECM is actually accurate.

If you do the race fuel thing and the tune is not to blame. Your engine may just be tired. I would do a leak down test at that point. That will tell you if you have excessive blow by.

I didn't look at your data logs. I just don't like looking at spreadsheets unless I absolutely must. Sorry.
PSolbergfan is offline   Reply With Quote
Old 11-19-2022, 12:08 PM   #3
PSolbergfan
Scooby Specialist
 
Member#: 112612
Join Date: Apr 2006
Chapter/Region: MWSOC
Location: Appleton,Wisconsin
Vehicle:
2010 Legacy 2.5 CBS
2002 Impreza WRX WRB

Default

When I had my hybrid tuned years ago I had a new Denso MAF installed on the car. My tuner was having issues with tuning so he took a known good O.E.M. MAF out of one of his cars and the tune went much better. So he replaced the Denso MAF with a new O.E.M. MAF (Yes, I know the Subaru MAF is made by Denso) and life is good. I see you changed your MAF and AF sensor within the last year. Those are two critical sensors. Did you go with good, Denso sensors or O.E.M.? I would NOT trust anything else.

1. You may have gotten a bad tank of fuel.
2. Buy 5 gallons of racing fuel and mix it with the highest octane pump fuel you can buy. E10 is okay. See if your problem still exists. This will determine if you have a tuning/ mechanical issue or just a bad tank of fuel.
3.Did you do a ECM reset? That may help.
4.Does your DP have an accommodation for another A/F/ sensor? If so, install one. A.E.M. makes a good kit with gauge. It's redundant but you'll be able to see if the sensor feeding the ECM is actually accurate.

If you do the race fuel thing and the tune is not to blame. Your engine may just be tired. I would do a leak down test at that point. That will tell you if you have excessive blow by.

I didn't look at your data logs. I just don't like looking at spreadsheets unless I absolutely must. Sorry.
PSolbergfan is offline   Reply With Quote
Old 11-25-2022, 11:37 AM   #4
nathanbunge
Scooby Newbie
 
Member#: 530551
Join Date: Jun 2022
Default Fuel worked

Forgot to post this earlier, but I drove the car lightly until gas was out and then filled tank up with a different brand fuel and knock went away. After a lot of driving I could see that it was adding timing back in, but DAM was still at 13. So i reset ECU and it went right back up to 16. Been keeping an eye on it and no knock so far, so I'm pretty certain it was just bad fuel. I'm 99% sure I selected 93 grade fuel when I got it, but I guess maybe it gave the the wrong one or it was just bad, idk. Thanks!
nathanbunge 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 03:58 AM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2024 Axivo Inc.
Copyright ©1999 - 2019, North American Subaru Impreza Owners Club, Inc.

As an Amazon Associate I earn from qualifying purchases.

When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission
Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.