Welcome to the North American Subaru Impreza Owners Club Tuesday August 22, 2017
Home Forums WikiNASIOC Products Store Modifications Upgrade Garage
Go Back   NASIOC > NASIOC Technical > Engine Management & Tuning > Open Source 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. 
Thread Tools Display Modes
Old 11-06-2009, 03:51 AM   #1
Scooby Specialist
Member#: 105629
Join Date: Jan 2006
Chapter/Region: NWIC
Location: Corvallis, OR
2006 300c SRT8

Default Leak causing knock?

I've had a couple CEL's lately that have all been MAF related. I know that the MAF is fine, but after pressurizing the inlet to find leaks, I've found one on one of the elbows coming off the inlet. Also, some of the IC couplers seem to be a bit worn, and might be leaking as well.

Would a leak in the intake system cause a lean condition, which would in turn cause knocking and/or lower IAM's? Recently I've done some logging, and definitely have some knock...I'm just hoping that maybe a leak somewhere might cause this...at least it'd be a relatively easy fix. Any ideas?
* Registered users of the site do not see these ads.
dlh1999 is offline   Reply With Quote
Sponsored Links
* Registered users of the site do not see these ads.
Old 11-16-2009, 06:15 PM   #2
Scooby Specialist
Member#: 31573
Join Date: Jan 2003
Chapter/Region: NWIC
Location: land of kirk
I found the
meaning of life!


I am curious about OP question that as well.

Also, how did you search for leaks? In the rx7 days I used to spray wd40 on joints and listen for idle to go up. It doesnt seem very precise, but it would find some larger leaks.

awd4ever is offline   Reply With Quote
Old 11-16-2009, 07:20 PM   #3
NASIOC Supporter
Member#: 165749
Join Date: Dec 2007
Chapter/Region: South East
Location: Central Floriderp

any leak after the MAF can cause problems, however with a turbo when under boost, leaks will result in less than the MAF measured amount of air reaching the cylinders (rich condition) and while under vacuum the opposite typically occurs.

A WB is highly recommended and really required to tune beyond CL maf scaling and OL/CL delay zero-ing
GrundleJuice is offline   Reply With Quote

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
Can a boost leak cause a knock? Deserted1 Engine Management & Tuning 2 04-18-2009 01:02 PM
Major Pre-turbo exhaust leak - cause car to knock? BlackoutWRX Factory 2.0L Turbo Powertrain (EJ Series Factory 2.0L Turbo) 2 05-27-2007 03:18 PM
Bad plugs causing knock/misfire? CreeeV15 Factory 2.0L Turbo Powertrain (EJ Series Factory 2.0L Turbo) 9 03-08-2007 11:25 PM
can this code cause knock sr55stiguy Factory 2.5L Turbo Powertrain (EJ Series Factory 2.5L Turbo) 2 04-11-2006 10:09 AM
Could a 3 cent screw and an idiot be causing knock? srf Engine Management & Tuning 8 07-31-2005 10:39 PM

All times are GMT -4. The time now is 09:19 AM.

Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2017 Axivo Inc.
Copyright ©1999 - 2017, North American Subaru Impreza Owners Club, Inc.