Welcome to the North American Subaru Impreza Owners Club Tuesday July 29, 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 > Factory 2.0L Turbo 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 08-29-2012, 03:35 PM   #501
Wagon Of Fury
Scooby Newbie
 
Member#: 47982
Join Date: Nov 2003
Chapter/Region: Tri-State
Default

I think I just fixed this problem after living with it for about two months. If I did, I will hang my head in shame for the simplicity of it.
* Registered users of the site do not see these ads.
Wagon Of Fury is offline   Reply With Quote
Old 09-19-2012, 11:24 PM   #502
Scubydood
Scooby Newbie
 
Member#: 165503
Join Date: Nov 2007
Vehicle:
2005 Sti
WRB

Default

I recently started getting this code too. Subaru thought it was either the maf or afr sensor. Had tuner check it out and code still came back when they tested with new parts. They said my DW850's are going bad? I bought them new only two tears ago.
Scubydood is offline   Reply With Quote
Old 09-20-2012, 08:42 AM   #503
Wagon Of Fury
Scooby Newbie
 
Member#: 47982
Join Date: Nov 2003
Chapter/Region: Tri-State
Default

Check the simple stuff, like vacuum leaks. Your injectors ? Unlikely, but send them off to RC for cleaning if it eases your mind.
Wagon Of Fury is offline   Reply With Quote
Old 10-24-2012, 11:39 AM   #504
kurtwz
Scooby Newbie
 
Member#: 95420
Join Date: Sep 2005
Default

Would running the car w/o the restrictor pill in place cause this code? Also, if i would fix the problem and drive the car w/o clearing the code on a scanner, how long would the car take to clear the code itself?

Last edited by kurtwz; 10-24-2012 at 11:46 AM.
kurtwz is offline   Reply With Quote
Old 10-25-2012, 10:03 AM   #505
kurtwz
Scooby Newbie
 
Member#: 95420
Join Date: Sep 2005
Default

Still need to know how long you'd have to drive the car with the problem fixed for the check engine light to turn off. Thanks
kurtwz is offline   Reply With Quote
Old 10-25-2012, 10:37 AM   #506
Wagon Of Fury
Scooby Newbie
 
Member#: 47982
Join Date: Nov 2003
Chapter/Region: Tri-State
Default

Quote:
Originally Posted by kurtwz View Post
Would running the car w/o the restrictor pill in place cause this code? Also, if i would fix the problem and drive the car w/o clearing the code on a scanner, how long would the car take to clear the code itself?
Anything that messes with the air intake flow could cause this. Anything.

Quote:
Originally Posted by kurtwz View Post
Still need to know how long you'd have to drive the car with the problem fixed for the check engine light to turn off. Thanks
Depends on the type of CEL.
Buy a $45 scantool or go to VatoZone and let them clear it for you.
Or google OBD readiness
Wagon Of Fury is offline   Reply With Quote
Old 10-25-2012, 10:45 AM   #507
kurtwz
Scooby Newbie
 
Member#: 95420
Join Date: Sep 2005
Default

I’m wrestling with this problem. I have an 02 WRX w/ 101K mi. It used to be a stage 3 car (16G turbo, pink injectors, Walbro fuel pump), but I’ve reverted it back to stock. The car was not driven for a couple years before I just recently started driving it again and having problems with it. The car is now completely stock in terms of the powertrain. The installation of the injectors and stock fuel pump went well. Car is running great. Smooth strong power, smooth stable idle, no sputtering, etc.. The only complaint would be that the throttle response seems a little slow. About 150 miles ago I got the P0171 code and haven’t been able to fix it yet. Here’s what I’ve done:

1. Checked vacuum lines: checked all vacuum lines around turbo, IC, air intake. Everything seems good and tight.
2. Checked air box: tight.
3. MAF: cleaned thoroughly using MAF sensor cleaner.
4. PCV Valve: cleaned thoroughly using MAF sensor cleaner. I know it’s best to replace this since it’s only a couple bucks, but I didn’t have one on hand and the stores were closed, so I had to clean it. I DID notice that there was a fairly substantial amount of oil (I think it was oil) in the tubes that go from the PCV valve to the black plastic nozzle and in the tube from the black plastic nozzle to some other nozzle (on the air intake I think). That’s bad, right? Could that cause the P0171 code? There was so much oil that I think it got into the IC y-pipe. That possible?

I haven’t cleaned/replaced the MAF, O2 sensor, IACV, or MAP sensor. I want to try cheaper potential fixes before I start replacing parts. The IACV gasket is on order, so I plan on going that, tho.

Can anyone offer advice specific to my situation? Specifically I’d be interested to know whether you think the PCV valve being that messed up could cause the code. Also, I’d love to know how long after the root cause is fixed I can expect the light to turn itself off. THANKS!!!
kurtwz is offline   Reply With Quote
Old 10-25-2012, 10:46 AM   #508
kurtwz
Scooby Newbie
 
Member#: 95420
Join Date: Sep 2005
Default

Quote:
Originally Posted by Wagon Of Fury View Post
Anything that messes with the air intake flow could cause this. Anything.

Restrictor pill on order.

Depends on the type of CEL.
Buy a $45 scantool or go to VatoZone and let them clear it for you.
Or google OBD readiness
I have a scanner. It's P0171 error code.
kurtwz is offline   Reply With Quote
Old 10-25-2012, 03:28 PM   #509
J. Steinbeck
Scooby Specialist
 
Member#: 140575
Join Date: Feb 2007
Location: Hotlanta, GA
Vehicle:
2007 Magnum SRT-8

Default

I got this code a couple of weeks ago after doing some work on my car. Car idled like ****.

Since I removed the intercooler, I assumed I must have created a post turbo intake leak of some kind. I reinstalled and removed the intercooler three times and looked EVERYWHERE under it trying to find what in the world I messed up.

Then... low and behold, while I was at work something occurred to me. I went back to the car, popped the hood, and there, directly in front of me, was the purge control solenoid on the front of the intake, pushed off slightly from its straw sized hose.

DOH! Turns out I was resting my palm in that area while I was working and knocked it loose. Put it back on, zip tied it tight (in other words, I turned the tie into a small hose clamp), and everything was back to normal.

The point in the story is to make sure you check around that thing, as it's easy to knock the little lines that go into and out of that round black piece loose, and they can definitely create a vacuum leak significant enough to cause this code.

Perhaps this has already been stated, but I was honestly too lazy to search back through the 500+ pages of this thread.
J. Steinbeck is offline   Reply With Quote
Old 10-25-2012, 03:48 PM   #510
kurtwz
Scooby Newbie
 
Member#: 95420
Join Date: Sep 2005
Default

Quote:
Originally Posted by J. Steinbeck View Post
Perhaps this has already been stated, but I was honestly too lazy to search back through the 500+ pages of this thread.
Thanks for the tips, Steinbeck. My car is idling and running all around great. Also, I've spent several hour under the hood at this point trying to fix this and don't think I'll find a loose hose at this point.

***UPDATE***
I just drove my car over lunch to get new tires. After I picked it up I noticed the check engine light was OFF. I went back and asked them whether they disconnected the battery/reset the ECU (just to be sure) and they said they did not. Then on the way back to work the light came back on after only 5 miles of driving. So I think I'm starting to have an impact, but it's not totally solved.

Anyone else have a situation where the light turns off, then comes back on very shortly thereafter? BTW, I scanned it just to make sure and it shows one fault of P0171 and one pending fault of P0171, so itís the same as the original code.
kurtwz is offline   Reply With Quote
Old 10-27-2012, 09:25 PM   #511
WickedTSI
Scooby Newbie
 
Member#: 186738
Join Date: Aug 2008
Chapter/Region: South East
Location: Gainesville Fla / Jersey Shore
Vehicle:
2002 wrx
mbp

Default

Had this code for about 2 weeks. It turned out to be a bad Maf, car runs great now.
WickedTSI is offline   Reply With Quote
Old 11-23-2012, 01:04 PM   #512
Sindvs
Scooby Newbie
 
Member#: 334360
Join Date: Oct 2012
Vehicle:
2007 suabru wrx sti
pearl

Default

i recently bought a 2007 sti and it has a aps cold air intake the previous owner installed and i drove it for a couple days and i got a cel i got the infamous p0171. i am not sure if its the CAI but i looked at the aps website and it says tuning maybe required, so i was thinking of buying a cobb access port do a data log and have some one make me a map do you think this will work?
Sindvs is offline   Reply With Quote
Old 11-23-2012, 06:11 PM   #513
Wagon Of Fury
Scooby Newbie
 
Member#: 47982
Join Date: Nov 2003
Chapter/Region: Tri-State
Default

Quote:
Originally Posted by Sindvs View Post
i recently bought a 2007 sti and it has a aps cold air intake the previous owner installed and i drove it for a couple days and i got a cel i got the infamous p0171. i am not sure if its the CAI but i looked at the aps website and it says tuning maybe required, so i was thinking of buying a cobb access port do a data log and have some one make me a map do you think this will work?
If you have a boost leak somewhere, you will get this. So re-read the thread and find your leak. Or, spend hundreds of dollars on a AP and a tune, and then still have a leak, which will have to be found, before you get a (re) retune.
Wagon Of Fury is offline   Reply With Quote
Old 11-26-2012, 11:55 AM   #514
Timmy_M2000
Scooby Specialist
 
Member#: 289514
Join Date: Jul 2011
Chapter/Region: South East
Location: Jax, FL
Vehicle:
2003 WRX Sedan
Ralley Blue

Default

Quote:
Originally Posted by Wagon Of Fury

If you have a boost leak somewhere, you will get this. So re-read the thread and find your leak. Or, spend hundreds of dollars on a AP and a tune, and then still have a leak, which will have to be found, before you get a (re) retune.
True. I FINALLY sourced mine to pinholes on the weld in my header right in front of my AFR, in conjunction with a couple other small leaks. Boost checks are a solid way to find them. Many different apparatus' can be used to find them. I used one from dnorton here on the forums. Worked great, found all my topside leaks at least.
Timmy_M2000 is offline   Reply With Quote
Old 12-03-2012, 08:45 AM   #515
SimonTuffGuy
Scooby Newbie
 
Member#: 28550
Join Date: Nov 2002
Chapter/Region: MAIC
Location: Central PA
Vehicle:
2002 WRX Wagon
Black

Default

Quote:
Originally Posted by kurtwz View Post
Anyone else have a situation where the light turns off, then comes back on very shortly thereafter? BTW, I scanned it just to make sure and it shows one fault of P0171 and one pending fault of P0171, so itís the same as the original code.
Mine went off twice during the time that I had the CEL, but it only seemed to go off when I drove in heavy rain. After it dried up, the CEL returned.

I finally found the culprit of mine... I've got a stock 02 WRX with 135k on it. I replaced the fuel filter and ran a good bottle of cleaner through it. Visually checked all the lines that I could see for cracks or being disconnected, listened, nothing. (I did have a leak from when I installed my OEM boost gauge. It was on the inside where the kit I bought connected to the stock hose, and I resolved that with a heavy duty twist clamp.) I cleaned the air filter, which was pretty crusty and sprayed the MAF with the special cleaner. That was also coated with the same crud that was on the filter. So - CEL came back after those cheapy fixes, so I opted for the O2 sensor next, since it was the next cheapest option. $119 off Amazon and an hour install, the CEL returned this weekend after my 100 mile mark and the car continued to "hesitate"... It seemed like under full boost in any of the gears, but I saw it mostly in 3rd-5th when going up a hill... It just "chugged" almost.

Had a friend pick up an 02 WRX earlier this week, so I went to meet up with him on Sunday. We swapped MAFs for the day and I took the car out to camp and for a 120~ mile trip. Instantly, the car responded better, no chugging, no hesitation... Realistically, I went 120~ miles and should've gone further, but the wife wasn't happy after the 300 mile trip from Saturday and had enough on Sunday. Anyways - I ordered up the Denso MAF last night from Advance, since they were running a 20% off sale and it should be here sometime this week. All in time to get my inspection done, without having to reset the code, hit 80 miles and hope that the light didn't come back on before they got it on the computer.

Thanks for the help and suggestion of this thread... And good luck to anyone battling this damn code.
SimonTuffGuy is offline   Reply With Quote
Old 12-04-2012, 12:21 PM   #516
czum09
Scooby Newbie
 
Member#: 336078
Join Date: Oct 2012
Chapter/Region: MWSOC
Location: Cedar Rapids, IA
Vehicle:
2002 WRX
WRB

Default

So my car has had this CEL for about a month... heres my symptoms, bad throttle response, idle feels like its on three cylinders, and sometimes the rpms dip to like 200 rpm. Any ideas?
czum09 is offline   Reply With Quote
Old 12-05-2012, 06:45 PM   #517
ceasar
Scooby Newbie
 
Member#: 296843
Join Date: Oct 2011
Chapter/Region: SCIC
Location: oc
Vehicle:
02 wrx JDM
MBP

Default

Quote:
Originally Posted by czum09 View Post
So my car has had this CEL for about a month... heres my symptoms, bad throttle response, idle feels like its on three cylinders, and sometimes the rpms dip to like 200 rpm. Any ideas?
Clean ur maf sensor. if it doesnt help use ur friend's maf for like 10 min, so u r able to tell if ur maf is shot or not. Post results.
ceasar is offline   Reply With Quote
Old 12-06-2012, 09:26 AM   #518
czum09
Scooby Newbie
 
Member#: 336078
Join Date: Oct 2012
Chapter/Region: MWSOC
Location: Cedar Rapids, IA
Vehicle:
2002 WRX
WRB

Default

I cleaned it and the CEL still came back after 15 miles of city driving. I will see if I can use my buddies. Also sometimes the car over boosts... It's so weird.
czum09 is offline   Reply With Quote
Old 12-14-2012, 11:03 PM   #519
Illest_WRX209
Scooby Newbie
 
Member#: 340577
Join Date: Dec 2012
Default

I practically checked every instruction on this thread and I still cant seem to find the problem. The previous owner of my car had not driven the car for over a year and when I got it I read the codes it said bank 1 too lean and cylinder 1 and 3 misfire . I've replaced the front o2 sensor spark plugs fuel filter checked all vacuum lines grounds they all came out good. Maf is cleaned checked to see if the intake were mounted on correct. Any ideas that the injectors or coil plugs could be the culprit . After all the car has been sitting for a year. And also I may add it runs perfectly fine but when it's below a quarter tank it tends to jerk like as if there's a fuel cut somewhere. Any suggestions would be highly appreciated . Thanks , Johnny
Illest_WRX209 is offline   Reply With Quote
Old 01-22-2013, 03:09 PM   #520
devlmaycry
Scooby Newbie
 
Member#: 309878
Join Date: Feb 2012
Chapter/Region: South East
Location: Rome, GA
Vehicle:
2002 WRX
PSM

Default

Had several codes after the TGV delete, even though I left my motors and rods in, including this one. Fixed all of the other codes related to the TGV being sticky except the P0171 until I read this thread. Tracked it down in about 5 minutes. The FPR hose had gotten knocked off or not hooked back up. Fixed it and the code hasn't come back. Great thread!
devlmaycry is offline   Reply With Quote
Old 02-05-2013, 01:37 AM   #521
st267
Scooby Newbie
 
Member#: 345988
Join Date: Feb 2013
Default

Thanks so much for this write up. Finished a clutch job Sunday started the car up and it ran like hell. ROUGH.. barely idling, staled once. Finally threw the P 0171 code after about 5 miles of driving. Took 10 mins Monday night to quickly check the air box and hoses in sight. Low and behold, on that little blue T connector between the bottom front of the IC and the intake manifold, had one of the vacuum lines off. Reconnected it and the rest is history
st267 is offline   Reply With Quote
Old 02-05-2013, 11:46 PM   #522
txl146
Scooby Guru
 
Member#: 32459
Join Date: Feb 2003
Chapter/Region: Tri-State
Location: NY
Vehicle:
02 WRX VF34
Junior Tuned 301whp

Default

Here is how I fixed my P0171 CEL (repost).

txl146 is offline   Reply With Quote
Old 02-06-2013, 01:31 PM   #523
mmiller2002
Scooby Specialist
 
Member#: 159286
Join Date: Sep 2007
Chapter/Region: TXIC
Location: Fort Worth, TX
Vehicle:
2002 WRX Wagon,Com-C
RCE wgn sprngs/Konis/H6

Default

WOW, that's a lot of $$! At what step was the MAF replaced the first time?
mmiller2002 is offline   Reply With Quote
Old 02-07-2013, 12:10 AM   #524
txl146
Scooby Guru
 
Member#: 32459
Join Date: Feb 2003
Chapter/Region: Tri-State
Location: NY
Vehicle:
02 WRX VF34
Junior Tuned 301whp

Default

MAF was replaced with another one probably a year before car started to have CEL problem. Never thought it was bad MAF since it looked almost new.
txl146 is offline   Reply With Quote
Old 02-07-2013, 12:33 AM   #525
Gethin
Scooby Specialist
 
Member#: 2998
Join Date: Nov 2000
Chapter/Region: VIC
Location: BC
Vehicle:
2002 WRX
WRB

Default

re clocking my IACV actuator fixed mine. I tried a new front o2, MAF sensor, smoke leak test (nothing found) , IACV gasket, cleaning IACV by removing the actuator, cleaning with qtips etc, checking all hoses etc etc etc but it always came back. I think it initially was caused by a bad front o2 which I replaced. Symptoms included a lumpy idle, especially when cold.

I ended up loosening the IACV actuator bolts, clocking it until the gap between the spinning edge and the housing was as small as possible, then tightening the actuator bolts (make sure the tab that protrudes out of the spindle fits into the cap correctly if you take the actuator off) and bolting it all back up. I must have put it back incorrectly last time when trouble shooting the whole affair.

Idle is now rock solid, and no more CEL.

Last edited by Gethin; 02-07-2013 at 01:05 AM. Reason: spelling
Gethin 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
Everything you ever wanted to know about anything ever made......ever Hester Prynne Off-Topic 12 11-05-2008 05:57 PM
OT Non-Gun Nuts: Everything you ever wanted to know but were afraid to ask (or try) Janq Off-Topic 47 12-29-2006 01:23 PM
Everything you ever wanted to know about exaust systems Back Road Runner Normally Aspirated Powertrain 9 10-24-2006 09:59 PM
('93-'01) Everything you ever wanted to know about Subarus... Porsche914boxer4 Impreza Forum 15 07-23-2001 09:17 PM
Everything you ever wanted to know about WRX exhauasts (old model) --> rao Normally Aspirated Powertrain 5 02-12-2001 08:56 PM


All times are GMT -4. The time now is 08:35 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.