Welcome to the North American Subaru Impreza Owners Club Wednesday July 23, 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 02-13-2011, 08:02 PM   #1
PULMEOVR
Scooby Newbie
 
Member#: 222724
Join Date: Sep 2009
Chapter/Region: E. Canada
Location: Ottawa, Ontario Canada
Vehicle:
2005 Impreza RS
Regal Blue

Have a Nice Day? Constant 02 Sensor failing?

Hi Guys,

I seem to keep fouling my front O2 sensor. I bought the car at 93,000km and replaced my first front O2 sensor at 99,000 km. At 109,000 km I could tell the O2 sensor was again slowly failing (low idle, bucking at low RPM etc). A few months later (today) at 117,800 I finally threw a code. I haven't pulled the code yet, but it has all the symptoms of a failed sensor.

Now my question is this ...

My car burns oil at a rate of about 1 quart/5,000km. This to me does not seem excessive. However, this oil burning seems to be fouling my front sensor over time. What should I be doing to fix this problem? I'm hoping there is another option besides tearing down the engine, replacing the rings etc. I've read that I should replace the sensor with Subaru OEM. I don't want to be replacing the sensor every 10,000km at a cost of $600.

Opinions? Anyone else having this problem? A quick search on here says yes, but doesn't seem to answer the above questions.

Thanks for your help ladies & gents.

EDIT: <--- '05 Impreza RS. 100% stock.
* Registered users of the site do not see these ads.
PULMEOVR is offline   Reply With Quote
Old 02-13-2011, 08:12 PM   #2
Gott-Wagons?
Scooby Newbie
 
Member#: 253412
Join Date: Jul 2010
Location: Jonesboro
Vehicle:
2002 WRX and Outback
silver

Default

my 02 bugeye has the same problem, you may want to check your connections on your sensors. also check the seals where the 02 sensors connect to the pipes. mine managed to catch some water and all hell broke loose with the engine.

that may help you
Gott-Wagons? is offline   Reply With Quote
Old 02-13-2011, 08:37 PM   #3
RaceFaceXC
NASIOC Supporter
 
Member#: 165749
Join Date: Dec 2007
Chapter/Region: South East
Location: stupid Florida
Vehicle:
2007 No YELLING
on the bus!

Default

The oem sensor is def the one to use but it can be had for much less than $600. I think you could find one of the same p/n for less than $100 with ease
RaceFaceXC is offline   Reply With Quote
Old 02-13-2011, 08:59 PM   #4
PULMEOVR
Scooby Newbie
 
Member#: 222724
Join Date: Sep 2009
Chapter/Region: E. Canada
Location: Ottawa, Ontario Canada
Vehicle:
2005 Impreza RS
Regal Blue

Default

Sorry, I meant $600 for the sensor & installation (labour rates are high in my area). It's too cold up here to do any work on the car myself right now. Unfortunately, I don't think this can wait until the spring. Bummer.

So, replace sensor with OEM. It will probably foul again within 20,000km. Any solutions to the above problem besides an engine rebuild?
PULMEOVR is offline   Reply With Quote
Old 02-13-2011, 10:04 PM   #5
Back Road Runner
Scooby Guru
 
Member#: 60082
Join Date: Apr 2004
Chapter/Region: MWSOC
Location: Minnesota
Vehicle:
2004 Forester STI
Silver

Default

That shouldn't be enough oil to foul a sensor that fast. I mean it's a worn motor, but that amount of oil consumption isn't excessive enough to do it that quick, maybe half a year or a year, but just a few months seems quick.

One option you have is to reduce your consumption. If you're running a 0w30, step to a 0w40. Using an oil that's a little bit thicker hot will drop the consumption considerably. This can help with blowby if you're really beating on the motor as well as losses from a head gasket leak. There's even a 0w50 available by Eneos if needed. Each step up pretty much halves consumption, but the thicker oil when hot also means oil flow is lower through the bearings which means less cooling. It's not really an issue outside of sports use, and you're not exactly in blistering heat.

The sensor is cheap, like $80. It screws off, screws on. You will have to buy a tool to remove it, but that might cost you $5. $600 for this work is a joke and a complete rip-off. It's a 10 minute job that they could charge at most 1 hour for (whatever the book says) at $80 or $100. If the labor rate is higher than that, they are royally ripping you off. The mechanic might see $12-$15 of that, maybe. The rest is profit. You might see a $200 bill for part + labor. I guess I don't know how $600 comes about.
Back Road Runner is offline   Reply With Quote
Old 02-13-2011, 11:42 PM   #6
Wrencher86
Scooby Newbie
 
Member#: 250463
Join Date: Jun 2010
Location: Evanston, Il
Vehicle:
2010 Impreza 2.5i
Silver

Default

Depending on where you're at, an $80 dollar shop rate is suspiciously cheap. The shop I'm at is about $120 an hour and that's on the lower side of average for my area. Shop overhead is a lot higher than most people think. The flat rate techs I work with also make about $25-$30 per book hour. I'm hourly at $15 and I can only assume, since I'm the newest employee, that I make the least of the hourly guys.

Anyway, more on topic: It shouldn't be a $600 job, even in Canadian dollars. The sensors aren't that hard to get to. You could probably do it yourself. An O2 sensor socket certainly makes the job easier, but it's completely doable with a 7/8ths wrench (that's sort of a guess. I've never had to change an O2 on a Subaru).

I'm not sure why the sensor would be failing that quickly. I know O2s don't like silicone but I'm not sure how that would be getting into your engine.
Wrencher86 is offline   Reply With Quote
Old 02-14-2011, 08:10 AM   #7
gmullin
Scooby Newbie
 
Member#: 271800
Join Date: Jan 2011
Default h

go to sears and buy eather a 7/8 wrench or a 22mm make sure its a 6 point box end. then get some muskels, get under the car and unscrew it.... have you looked at your plugs latley they usilly are the culprit of oil loss in a stock motor.the rings only allow a bit of oil by and if the plug gets slightly fouled or a crack in the porclin or has carbin tracking it wont burn all the fuel/oil causing you to have o2 and catilitic converter problems.... and if not all the fuel gets burned the cylinder dosent get to the corect temputure to seal the rings
gmullin is offline   Reply With Quote
Old 02-16-2011, 12:16 PM   #8
PULMEOVR
Scooby Newbie
 
Member#: 222724
Join Date: Sep 2009
Chapter/Region: E. Canada
Location: Ottawa, Ontario Canada
Vehicle:
2005 Impreza RS
Regal Blue

Default

Update:

I had the codes pulled and it turned out it wasn't a failed oxygen sensor after all. The codes were for a misfire on cylinders 1 & 3. I didn't really suspect a misfire at first sign of the problem as I just replaced my ignition coil & wires in the Fall (shop). I had water misted on the wires today and I could see an electrical arch coming from a crack on the wires housing leading to cylinders 1 & 3. So I brought it to the shop and had them replace the ignition coil (better safe then sorry) & wires (both under warranty).

My PCV valve was also clogged and not functioning properly. I was surprised! I imagine that helped contribute to my high oil consumption.

Thanks for everyones help.
PULMEOVR is offline   Reply With Quote
Old 09-21-2012, 11:52 AM   #9
ronlocus
Scooby Newbie
 
Member#: 213198
Join Date: Jun 2009
Chapter/Region: NESIC
Location: wallkill ny
Vehicle:
2002 impreza
silver

Default

burning that much oil has a cumulative effect on your cat and one qt every 3000 miles is a fair amount. your cat is fouled and any additional oil just gets into your 02 sensors. i had this same prob. I'm surprised you haven't gotten any cat codes for cat efficiency. The only way to truly fix this problem, is to stop the engine from burning oil, ie a rebuild and a new cat. Subaru recomends a 5w/30 oil. O2 sensors come with a connector which are much more expensive. One with just the wires are much cheaper, and the plug must be spliced properly. You must use a 6 point wrench to remove as a soccket will not fit over the wires. Time for a new car! Unless you want to sink mad money into this one
ronlocus 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
Constant Speed sensor alejo Brakes, Steering & Suspension 1 06-10-2010 11:29 PM
Front 02 Sensor,Rear 02 Sensor,MAF Sensor,Blox Shift Knob,SPT Oil Cap, bunch of stuff TopEndPull Engine/Power/Exhaust 11 08-14-2009 05:48 PM
WTB: 02-07 Maf Sensor, 04-07 Sti or 06-07 WRX 02 Sensor. TopEndPull TXIC Private Classifieds 1 07-26-2008 09:54 AM
TGV sensors FAIL emissions Shifty9 Newbies & FAQs 5 12-23-2006 03:56 PM
Oem 02 front sensor Or Wideband 02 sensor Fast_Wrx62 Factory 2.0L Turbo Powertrain 4 10-06-2006 09:58 AM


All times are GMT -4. The time now is 05:58 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.