Jump to content


Welcome to Ultimate Subaru Message Board, my lurker friend!

Welcome to Ultimate Subaru Message Board, an unparalleled Subaru community full of the greatest Subaru gurus and modders on the planet! We offer technical information and discussion about all things Subaru, the best and most popular all wheel drive vehicles ever created.

We offer all this information for free to everyone, even lurkers like you! All we ask in return is that you sign up and give back some of what you get out - without our awesome registered users none of this would be possible! Plus, you get way more great stuff as a member! Lurk to lose, participate to WIN*!
  • Say hello and join the conversation
  • Subscribe to topics and forums to get automatic updates
  • Get your own profile and make new friends
  • Classifieds with all sorts of Subaru goodies
  • Photo hosting in our gallery
  • Meet other cool people with cool cars
Seriously, what are you waiting for? Make your life more fulfilling and join today! You and your Subaru won't regret it, we guarantee** it.

* The joy of participation and being generally awesome constitutes winning
** Not an actual guarantee, but seriously, you probably won't regret it!

Serving the Subaru Community since May 18th, 1998!

Guest Message by DevFuse
 

Photo
* * * * * 1 votes

Knock sensor 101 and replacement


  • Please log in to reply
63 replies to this topic

#51 casm

casm

    The Timex of Lifters

  • Members
  • 190 posts
  • Seattle, Washington

Posted 24 March 2013 - 01:30 PM

Question regarding the clocking of the sensor: looking at the one on my '99 Forester S (EJ25, N/A) from the front of the engine, the electrical connector is set at about the 10 o'clock position.  From the photos earlier in the thread of the EJ22, it looks to be somewhere around 4 o'clock - or roughly 180 degrees opposite where mine is.  Is the orientation on mine correct, or should it be set at some other position?  The new sensor is shipping out tomorrow, and I'd really rather not screw this up when I do the replacement.



#52 Fairtax4me

Fairtax4me

    Su bah roo'n

  • Gold Subscribers
  • 8,725 posts
  • Charlottesburg, VA

Posted 24 March 2013 - 07:26 PM

Installation pictures were taken with the front of the engine (belts) at 12 o'clock, rear of the engine (bellhousing) at 6 o'clock.
Looking from the front the wire should be clocked at about 10:30.
The "safe" area is fairly obvious once the old sensor is removed.

#53 casm

casm

    The Timex of Lifters

  • Members
  • 190 posts
  • Seattle, Washington

Posted 25 March 2013 - 09:17 PM

Installation pictures were taken with the front of the engine (belts) at 12 o'clock, rear of the engine (bellhousing) at 6 o'clock.
Looking from the front the wire should be clocked at about 10:30.
The "safe" area is fairly obvious once the old sensor is removed.

 

Awesome, and thanks.  That jives with what I'm looking at from the front, so good to know.



#54 DawnTreader

DawnTreader

    Newbie

  • Members
  • Pip
  • 2 posts
  • Vancouver BC

Posted 29 August 2013 - 04:21 PM

Bravo-- great initial post-- thank you. Cautionary tale though: I'm here because before I bought my MY01 Forester a shop replaced the knock sensor, and incidentally put it back in that alternative hole higher on the block and closer to the driver's side. I'd been wondering what had been removed from the obvious clean spot lower on the block. While there was no CEL, the car always had a detonation on upshifts and hesitation at low revs in 1st and 2nd gear. I thought it was just part of its personality. :) Dealer pointed out the sensor position anomaly, and since I've moved it back down the pinging is gone and it runs MUCH smoother. I conclude for whatever reason the sensor wasn't detecting the knocks properly in the higher up position, even though they'd cleaned the hole and block surface well.   



#55 Fairtax4me

Fairtax4me

    Su bah roo'n

  • Gold Subscribers
  • 8,725 posts
  • Charlottesburg, VA

Posted 29 August 2013 - 07:56 PM

Great to hear some feedback about the alternative mounting of the sensor.

How long did you have the car before taking it to the dealer? Had it been pinging the entire time?
Was there another issue that prompted the dealer visit? A check engine light or some other condition which would require the ECU to be reset or the battery to be unhooked?
How long has it been since the dealer visit?

#56 subarubino

subarubino

    Newbie

  • Members
  • Pip
  • 3 posts
  • Sultan, WA

Posted 21 December 2013 - 05:56 PM

I've been experiencing problems with my '98 OBS, code for knock sensor came up, replaced it, nothing. The car sometimes runs as a new car, then for no reason at all, starts misfiring, bucking, etc. I am stumped. :( Nice write up here, I followed the directions to the T



#57 n00baru

n00baru

    Newbie

  • Members
  • Pip
  • 3 posts
  • Salt Lake City, Utah

Posted 08 March 2014 - 07:47 PM

Hi there.  Very informative thread.  This is my first post to the forum.  My mother has a 2000 Outback Limited sedan and she got a CEL on and off for six months or so, she took it to the dealer and they recommended a new knock sensor and want to charge her $380 for the pleasure.  I've been trying to save her money and do some stuff for her and this seems like a fairly easy fix but one thing intimidates me and that is getting the orientation of the wire correct.  I look at the original post and I'm still a bit confused.  Any tips on ways to get the angle and orientation exactly correct?  I really don't want to screw up anything.  

 

ALSO, are the sensors available on ebay just as good as the OEM?  The parts dept at the dealer wants $118 for the sensor and I see they are $10 on ebay.  Quite a difference.  

 

Thanks in advance.  



#58 fishy

fishy

    USMB is life!

  • Members
  • 260 posts
  • Nova Scotia, Canada

Posted 08 March 2014 - 08:04 PM

Hi there.  Very informative thread.  This is my first post to the forum.  My mother has a 2000 Outback Limited sedan and she got a CEL on and off for six months or so, she took it to the dealer and they recommended a new knock sensor and want to charge her $380 for the pleasure.  I've been trying to save her money and do some stuff for her and this seems like a fairly easy fix but one thing intimidates me and that is getting the orientation of the wire correct.  I look at the original post and I'm still a bit confused.  Any tips on ways to get the angle and orientation exactly correct?  I really don't want to screw up anything.  

 

ALSO, are the sensors available on ebay just as good as the OEM?  The parts dept at the dealer wants $118 for the sensor and I see they are $10 on ebay.  Quite a difference.  

 

Thanks in advance.  


The dealer probably wants to pull the intake manifold to do the job or something... 
I don't know if the ebay sensors are "just as good" as OEM but in my experience they are "good enough". I've got a $15 ebay sensor in my car and I've probably put 10,000km on it by now with no troubles. 
As with many things I made a little video about the replacement process. Part of the video is a discussion about the orientation of the sensor, maybe it will help you out:



#59 n00baru

n00baru

    Newbie

  • Members
  • Pip
  • 3 posts
  • Salt Lake City, Utah

Posted 08 March 2014 - 08:39 PM

Hey fishy.  I actually watched your video the other day.  I found it on youtube before I joined the forum.  Thanks for making it!   I guess I'm just a very literal person and the wire coming off the sensor is what I can't quite understand.  I'll take lots of pics of how it's on there now and just try to match it up the best I can.  

 

Thanks again.  



#60 Olnick

Olnick

    Ol' Subaru Guy

  • Members
  • 2,579 posts
  • Honolulu HI

Posted 09 March 2014 - 12:17 AM

Welcome aboard n00baru!  Don't obsess over getting "the proper angle."  The reason is simply to get the sensor sitting flush and flat on the engine block.  Put the new sensor down there at approximately the correct angle then turn it slightly side-to-side--you should be able to feel when it's sitting flat.

 

Re-read Fairtax's first post--he explains it very well.  And as he said, don't overtighten it or you can easily crack the new one.

 

Good luck!



#61 Fairtax4me

Fairtax4me

    Su bah roo'n

  • Gold Subscribers
  • 8,725 posts
  • Charlottesburg, VA

Posted 09 March 2014 - 10:27 AM

Any tips on ways to get the angle and orientation exactly correct? I really don't want to screw up anything.

ALSO, are the sensors available on ebay just as good as the OEM?


The angle doesn't have to be exactly exact. It'll make more sense when you get under the hood and look at it. Just note the orientation of the original sensor and try to get close to that with the new sensor.

Are the eBay sensors AS good? Probably not, but they're good enough. And for the cost, you can order 8 or 9 of them for less than 1 dealer part. If an eBay sensor lasts two years, and even if you get a dud, you're covered for 12,14, maybe 18 years, and you're still spending less than getting 1 from a dealer.

#62 n00baru

n00baru

    Newbie

  • Members
  • Pip
  • 3 posts
  • Salt Lake City, Utah

Posted 10 March 2014 - 12:06 AM

Thank you, Olnick and Fairtax4me.  That gives me some more confidence.  And as long as the cheapo ebay sensor doesn't hurt the performance of the car then I'll be very happy;  

 

And with the money I save I can totally justify buying a torque wrench, right?   :D



#63 Olnick

Olnick

    Ol' Subaru Guy

  • Members
  • 2,579 posts
  • Honolulu HI

Posted 10 March 2014 - 12:59 AM

Of course you can.  You have our permission.  :rolleyes:



#64 Fairtax4me

Fairtax4me

    Su bah roo'n

  • Gold Subscribers
  • 8,725 posts
  • Charlottesburg, VA

Posted 10 March 2014 - 12:19 PM

Thank you, Olnick and Fairtax4me. That gives me some more confidence. And as long as the cheapo ebay sensor doesn't hurt the performance of the car then I'll be very happy;

And with the money I save I can totally justify buying a torque wrench, right? :D

Any kind of tools are always a justified purchase! :D




0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users