Welcome to the North American Subaru Impreza Owners Club Thursday July 31, 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 > Normally Aspirated Powertrain

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 11-20-2000, 06:12 AM   #1
SSLegacyGT
Scooby Specialist
 
Member#: 2865
Join Date: Nov 2000
Chapter/Region: NWIC
Location: CdA, ID
Vehicle:
2006 Legacy 2.5i
Wagon, 5MT, Blue

Question Engine shudder/loss of power

I just returned from a trip to Vegas (from san diego). During that trip, my 97 Legacy GT (sedan) started acting up. When accelerating, I would experience a shuddering in the engine and dramatic loss of power between 1000-1500 rpms, but then the engine would seem to accelerate somewhat normally after that (sluggish but no shuddering). Small problem at first, but it has gotten worse. Any thoughts? I don't have any mods and I havent made in changes to the vehicle since I bought it.
* Registered users of the site do not see these ads.
SSLegacyGT is offline   Reply With Quote
Old 11-20-2000, 04:54 PM   #2
SSLegacyGT
Scooby Specialist
 
Member#: 2865
Join Date: Nov 2000
Chapter/Region: NWIC
Location: CdA, ID
Vehicle:
2006 Legacy 2.5i
Wagon, 5MT, Blue

Thumbs up

Yeah that sounds like what I've got from what I've read. But, I'm confused on the fix. I read like 3 or 4 different fixes, none of which seemed like they were a 100% sure problem solver. I tried reseting ECU and that didnt work. Took it down to a dealer, they wanted $70 just to look at it. So I guess I'll try some of the stuff mentioned before heading their way. Thanks for the suggestion.
SSLegacyGT is offline   Reply With Quote
Old 11-21-2000, 12:10 AM   #3
vinman
Scooby Newbie
 
Member#: 1425
Join Date: May 2000
Location: New Windsor, MD, USA
Vehicle:
2000 2.5RS
Aspen White

Post

I've seen posts about knock sensors and loss of power followed by normal acceleration. Try doing s search on knock sensors.
vinman is offline   Reply With Quote
Old 11-22-2000, 12:30 AM   #4
gumball
Scooby Specialist
 
Member#: 1209
Join Date: Apr 2000
Location: Wheaton, MD
Post

Hey there, if the problem is w/ the ECU (its not the knock sensor, its how the ECU over-reacts to the signal), then the ECU re-set should definitely work. I had the exact same problem, and it was between 1800 & 2500 rpms, like a giant hiccup in the engine.

What happens (and the Subaru TSB confirms this) is that the faulty ECUs (the Subaru TSB reccommended replacing the ECU, not the knock sensor) over-react to the Knock Sensor signal and retard your timing. The retarded timing gets stuck in memory. So technically, an ECU re-set should clear it out and performance, at least momentarily, should be better.

If it isn't, then I'd also look into-
Ignition wires, fuel filter, air filter, clogged PCV valve etc...

and incidentally, I DID do the electronic fix (in line resistor, I believe) which mellows-out the signal from the piezoelectric mic on the knock sensor, and it works Great!


[This message has been edited by gumball (edited November 21, 2000).]
gumball is offline   Reply With Quote
Old 11-23-2000, 07:34 AM   #5
SSLegacyGT
Scooby Specialist
 
Member#: 2865
Join Date: Nov 2000
Chapter/Region: NWIC
Location: CdA, ID
Vehicle:
2006 Legacy 2.5i
Wagon, 5MT, Blue

Post

Ok, thanks for the extra info, I think I will be getting thinline filter. Everythiing els you had mentioned I checked right off the bat. Thanks again...
SSLegacyGT is offline   Reply With Quote
Old 11-25-2000, 02:06 PM   #6
SSLegacyGT
Scooby Specialist
 
Member#: 2865
Join Date: Nov 2000
Chapter/Region: NWIC
Location: CdA, ID
Vehicle:
2006 Legacy 2.5i
Wagon, 5MT, Blue

Angry

Ok, now the check engine light has come on. Normal with this ecu/knock sensor problem? Or would it be something else?
SSLegacyGT is offline   Reply With Quote
Old 11-25-2000, 09:56 PM   #7
kelley nelson
Scooby Specialist
 
Member#: 135
Join Date: Aug 1999
Location: NJ
Post

Has your car been serviced recently? Check all of your plug wire connections to make sure that none are loose or off completely. Is your gas cap on tightly?

[This message has been edited by kelley nelson (edited November 25, 2000).]
kelley nelson 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
'07 WRX violent shudder and loss of power to rear end - axle? diff? DrnknZag Transmission (AT/MT) & Driveline 9 12-16-2009 11:35 PM
loss of power within 3 weeks of purchase KckAsX South East Region Forum 13 05-01-2002 04:13 PM
Recent loss of power Kachukaa General Forum Archive 0 01-15-2001 03:58 PM
Loss of power with Unorthodox pulley fellfrosch7 Car Audio, Video & Security 11 12-24-2000 10:09 PM
Loss of power and engine shudder SSLegacyGT Legacy Forum 12 11-23-2000 09:25 AM


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


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.