The Subaru SVX World Network   SVX Network Forums
Live Chat!
SVX or Subaru Links
Old Lockers
Photo Post
How-To Documents
Message Archive
SVX Shop Search
IRC users:

Go Back   The Subaru SVX World Network > SVX Main Forums > Technical Q & A

Reply
 
Thread Tools Display Modes
  #1  
Old 06-06-2005, 09:55 AM
Dza's Avatar
Dza Dza is offline
#073 of 301
 
Join Date: Oct 2003
Location: Regina, SK Canada
Posts: 386
CEL - Code 28, knock sensor. Help?

Hey guys, I need some help with a Check Engine Light code and resolution. I have to pass a federal inspection in the next 31 days, and a CEL probably won’t help much. I did a search and found some info on replacing knock sensors, but I jut have a few followup questions.

The code shows 28, Knock sensor 2 (LH): Abnormal voltage in knock sensor monitor circuit. Lucky me, the harder one to get at!

Here are my questions for you:
- Do I absolutely have to replace my knock sensor, or will replacing it just have the new sensor show a voltage error?
- Can I just reset the code and hope that it doesn't come back? Never done that before, but I found procedures on how to.
- I damaged the connector on the positive terminal of my battery the other day. Would this CEL be related at all?
- I hear that you’re supposed to, but is it mandatory to replace both knock sensors at the same time?

I just brought this car up from the US. She’s used to gas from her old home, but I was sure to use premium (higher octane) here with a shot from the bottle of fuel additive that the previous owner gave me. The gas was in the tank for 7 days before the CEL came on, so it may be unrelated.

I just need to get the car past inspection, and that would be difficult with a CEL showing. I hope that I don’t have to replace the knock sensors, but I will do it if I have to. Any info you guys can provide will be most appreciated.
__________________
Dan M.
Barcelona Red '93 AE #073 of 301, 168k miles.
Reply With Quote
  #2  
Old 06-06-2005, 10:20 AM
red95svx
Guest
 
Posts: n/a
1) The problem could be with the wiring that leads to the knock sensor...you'd have to test the sensor itself to determine that.

2) You could, but chances are it will return shortly.

3) No. A bad battery connection would cause multiple voltage problems, not just one.

4) No, you don't have to do both at once.


Hope this helps.



Dave
Reply With Quote
  #3  
Old 06-06-2005, 03:25 PM
Earthworm's Avatar
Earthworm Earthworm is offline
Meow!
 
Join Date: Mar 2002
Location: Winnipeg, Manitoba
Posts: 11,957
Send a message via ICQ to Earthworm Send a message via AIM to Earthworm Send a message via MSN to Earthworm Send a message via Yahoo to Earthworm Send a message via Skype™ to Earthworm
Have a look at the knock sensors. Both of mine were cracked but didn't throw an error code.
Reply With Quote
  #4  
Old 06-06-2005, 06:54 PM
Dza's Avatar
Dza Dza is offline
#073 of 301
 
Join Date: Oct 2003
Location: Regina, SK Canada
Posts: 386
OK, home now. Here's an update. I can hear a very noticeable TICK TICK TICK TICK when the car is running. It's coming from the general vicinity of the knock sensor that throws the code 28.

What can I do to fix this? Replace the knock sensor?
If I replace the knock sensor, won't the sensor just detect the engine knock again? (PS: I don't know anything about knock sensors).

Just need to get something done about this right away, so all help is welcome.
__________________
Dan M.
Barcelona Red '93 AE #073 of 301, 168k miles.
Reply With Quote
  #5  
Old 06-07-2005, 08:46 AM
Dza's Avatar
Dza Dza is offline
#073 of 301
 
Join Date: Oct 2003
Location: Regina, SK Canada
Posts: 386
When I clear the codes, I just get a 28 again right away. If someone can confirm that my problem will go away by replacing the knock sensor, I can get one ordered today.

What if it doesn't fix it, then what?
__________________
Dan M.
Barcelona Red '93 AE #073 of 301, 168k miles.
Reply With Quote
  #6  
Old 06-07-2005, 09:18 AM
red95svx
Guest
 
Posts: n/a
Quote:
Originally Posted by Dza
When I clear the codes, I just get a 28 again right away. If someone can confirm that my problem will go away by replacing the knock sensor, I can get one ordered today.

What if it doesn't fix it, then what?


Why wouldn't it fix your problem? You are running premium gas, right? So it can't be bad gas. The ECU is telling you what the problem is. Replace the sensor!



Dave

PS all Subaru's have a slight tick when running....it's normal.
Reply With Quote
  #7  
Old 06-07-2005, 11:55 AM
Earthworm's Avatar
Earthworm Earthworm is offline
Meow!
 
Join Date: Mar 2002
Location: Winnipeg, Manitoba
Posts: 11,957
Send a message via ICQ to Earthworm Send a message via AIM to Earthworm Send a message via MSN to Earthworm Send a message via Yahoo to Earthworm Send a message via Skype™ to Earthworm
Are you sure the tick is not just the injectors?
Reply With Quote
  #8  
Old 06-07-2005, 12:09 PM
Dza's Avatar
Dza Dza is offline
#073 of 301
 
Join Date: Oct 2003
Location: Regina, SK Canada
Posts: 386
Knock sensor odered from subaruparts.com. Thanks, guys.
__________________
Dan M.
Barcelona Red '93 AE #073 of 301, 168k miles.
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


All times are GMT -6. The time now is 06:49 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
© 2001-2015 SVX World Network
(208)-906-1122