Check Engine Light Advice - Jeep Wrangler Forum
Jeep Wrangler Forum

Go Back   Jeep Wrangler Forum > YJ Jeep Wrangler Forum > YJ Tech Forum

Join Wrangler Forum Today


Reply
 
Thread Tools

Please support our sponsors and let them know you heard about them on WranglerForum.com
Old 01-06-2011, 06:50 PM   #1
Newb
 
HokieStu's Avatar
 
Join Date: Jan 2011
Posts: 9
Check Engine Light Advice

1995 Wrangler Sahara, 200k miles

I had a hole in my exhaust just in front of the muffler. I ran it with the hole until the pipe finally broke free of the muffler. Not long after it broke free my "check engine" light came on. As soon as the engine is turned off the light goes out, but now comes back on after the engine warms up.

I installed a new cat converter & muffler. (nothing special, just one of those universal jobs) It sounds TONS better than it did before, but the check engine light came back on again.

I'm the original owner of this Jeep, the converter was the original, the muffler was the 2nd one.

Is there a reset?

HokieStu is offline   Quote Quick Reply
Old 01-06-2011, 07:01 PM   #2
Jeeper
 
60mg's Avatar
 
Join Date: Sep 2010
Location: Midwest
Posts: 845
Images: 18
Take the ground off of the battery for like 20 min. It should clean up codes. But if it comes back on you'll have to find the number do deal with the issue. There is a tread some where here with instructions on how to read codes.

__________________
95 YJ Rio Grande 2.5L 5-speed (We're at point "A". Where is point "B"? Who gives a sh..!? )
02 Triumph Sprint RS 955i (speed junky)
04 Honda Odyssey EX (parent-mobile)
60mg is offline   Quote Quick Reply
Old 01-08-2011, 06:56 PM   #3
Newb
 
HokieStu's Avatar
 
Join Date: Jan 2011
Posts: 9
Looks like I'm going to be searching for that thread...
HokieStu is offline   Quote Quick Reply
Old 01-08-2011, 07:25 PM   #4
J10
Jeeper
 
J10's Avatar
 
Join Date: Oct 2010
Posts: 210
Find the codes by turning your key to the on position (without starting it) and then off again three times on the third time leave in the on position and your codes will be blinked out via the check engine light.
I w0uld bet you get a 21 as well of course the 55 signaling the end of the codes
so for example the 21 will be a flash-flash-pause-flash
J10 is offline   Quote Quick Reply
Old 01-08-2011, 07:31 PM   #5
Jeeper
 
hannahuffster's Avatar
 
Join Date: Mar 2010
Location: Joplin, MO
Posts: 402
Images: 1
Post the codes you get I have a master list hard copy here by the computer (with many codes that arnt on some of the threads I have seen) and I will reference them for you if you are unable to find them...
__________________
J&D OFF-ROAD CLUB CHARTER MEMBER #10 OF S.W. MO [/CENTER]
hannahuffster is offline   Quote Quick Reply
Old 01-10-2011, 12:20 PM   #6
Newb
 
HokieStu's Avatar
 
Join Date: Jan 2011
Posts: 9
It's more difficult to read those flashes than I thought. I def get the 55 at the end. I'm pretty sure that I'm getting a 21 code at the beginning.

Does any of the codes seem to jive with the issue of my tailpipe breaking free? The light came on right after that.
HokieStu is offline   Quote Quick Reply
Old 01-10-2011, 06:54 PM   #7
J10
Jeeper
 
J10's Avatar
 
Join Date: Oct 2010
Posts: 210
21 is an O2 sensor not sure in the YJs but TJs have two and it seems like its always the one near the engine although mine was the downstream one after the cat
J10 is offline   Quote Quick Reply
Old 01-10-2011, 07:07 PM   #8
Jeeper
 
hannahuffster's Avatar
 
Join Date: Mar 2010
Location: Joplin, MO
Posts: 402
Images: 1
My YJ only has one O2 sensor. Reading the codes are a little tricky you need to do them a couple different times in a row to make sure you are getting the correct code count.
__________________
J&D OFF-ROAD CLUB CHARTER MEMBER #10 OF S.W. MO [/CENTER]
hannahuffster is offline   Quote Quick Reply
Old 01-11-2011, 08:49 AM   #9
Jeeper
 
YJPunisher213's Avatar
 
Join Date: Aug 2010
Location: Cincinnati, OH
Posts: 299
Images: 14
YJPunisher213 is offline   Quote Quick Reply
Old 01-02-2014, 08:02 PM   #10
Newb
 
Join Date: Jan 2014
Posts: 2
Help, I'm a girl

My 1995 Jeep Wrangler is flashing the check Engine light at me. I followed the instructions and got:

3 4 5 5

I know the last two fives signal the end. What do the first three numbers mean? Any help is much appreciated.
SaraRowan is offline   Quote Quick Reply
Old 01-03-2014, 12:09 AM   #11
jkp
Jeeper
 
Join Date: Mar 2010
Location: Warner Robins, GA
Posts: 409
__________________
'92 Islander
'06 Rubicon
jkp is offline   Quote Quick Reply
Old 01-04-2014, 09:40 AM   #12
Jeeper
 
samizdad's Avatar
 
Join Date: Nov 2013
Location: Albuquerque, NM
Posts: 419
You may have a "hard code" stored in the computer. It probably triggered when the muffler came apart. After fixing, it may not clear itself. You may have to find someone with an OBD 1 (OBD2 was 96 and up I believe) scan tool that can erase it. After that, if it comes back, you may look into replacing the o2 sensor as recommended.
__________________
97 TJ Sport, 4.0, AX-15, 4" lift, Rancho 5000's, Pro Comp ES2000 Stabilizer, JKS discos, T-Case drop, Rampage top, Sony/Sirius deck, 33" Firestone Destination MT's
samizdad is offline   Quote Quick Reply
Old 01-04-2014, 11:06 AM   #13
Jeeper
 
twister4399's Avatar
 
Join Date: Aug 2012
Posts: 224
Quote:
Originally Posted by jkp View Post
Sahara's have cruise and AC from factory. I didn't even know there was a code for cruise to trip the check engine light.
twister4399 is offline   Quote Quick Reply
Old 01-04-2014, 11:29 AM   #14
jkp
Jeeper
 
Join Date: Mar 2010
Location: Warner Robins, GA
Posts: 409
I couldn't remember if YJs had cruise from the factory or not.

My Islander has factory AC.
__________________
'92 Islander
'06 Rubicon
jkp is offline   Quote Quick Reply
Old 01-04-2014, 06:06 PM   #15
Jeeper
 
ThePhantomPatriot's Avatar
 
Join Date: Jul 2012
Location: Delta, PA
Posts: 259
Muffler wouldn't throw CEL. The only thing on the exhaust system that throws CEL is O2 sensor and for the yj's they are fairly cheap compared to other cars. I replaced mine when I replaced the exhaust.
__________________
1995 - 2.5L Low Output Wrongler
ThePhantomPatriot is offline   Quote Quick Reply
Old 01-12-2014, 08:14 AM   #16
Newb
 
Join Date: Jan 2014
Posts: 2
No I don't have cruise control. If it's just me exhaust, I can drive it anyways... Right?
SaraRowan is offline   Quote Quick Reply
Old 01-12-2014, 08:35 AM   #17
Jeeper
 
screamingmeme322's Avatar
 
Join Date: Jan 2014
Location: Des Moines Iowa
Posts: 19
I am having the same problem with the trouble codes. My Jeep was running a little rough on take off, the rpms would drop and it threw a code saying it was the throttle positioning sensor. I changed the TPS and it is still doing the same thing and throwing same code. I am determined to do all the work by myself on my new found obsession. Yes, I am a girl too so I would love all the suggestions I can get.
__________________
Brandie Johnson
screamingmeme322 is offline   Quote Quick Reply
Old 01-12-2014, 02:13 PM   #18
Jeeper
 
Pittsburghwrangler's Avatar
 
Join Date: Jun 2013
Location: Pittsburgh
Posts: 970
Quote:
Originally Posted by screamingmeme322 View Post
I am having the same problem with the trouble codes. My Jeep was running a little rough on take off, the rpms would drop and it threw a code saying it was the throttle positioning sensor. I changed the TPS and it is still doing the same thing and throwing same code. I am determined to do all the work by myself on my new found obsession. Yes, I am a girl too so I would love all the suggestions I can get.
How does the lead connecting to the sensor look? The contact inside of the opening could be fouled. And btw I love hearing about a woman doing her own auto work, bad ass!
__________________
1995 YJ Rio Grande 2.5l I4 Auto, random cheap mods, saving money for BDS (or OME still undecided) 2.5" lift
Pittsburghwrangler is online now   Quote Quick Reply
Old 01-12-2014, 02:19 PM   #19
2xs
Cali Smog Nazi.

WF Supporting Member
 
2xs's Avatar
 
Join Date: Jun 2011
Location: Santa Rosa, Ca.
Posts: 2,630
Images: 3
Any code is what the computer thinks is the problem, if you get a code for the TPS or O2 sensors, remember, the sensor itself is only one part of the circuit, you also have to make sure the wires to the computer are ok, all the connectors, and the computer itself....

Also, an O2 sensor code does not necessarily mean the O2 sensor is bad, it could be a vacuum leak causing the O2 to read lean, or a leaking fuel injector can cause a rich reading, both can throw and O2 code because the O2 reading does not change.

Other sensors can be affected by the supply voltage being low, if a TPS has a low input voltage, it cant send the correct signal back to the computer. The Computer sees a low TPS/IAT/MAP/ signal and can set a code for any of those all of those or none but have a drivability issue.
Grounds can also cause issues, a poor ground can cause a high reading.

Do you guys have a volt-ohm meter? even a cheap one can work.
__________________
'93 Black YJ, 4.0L AX15 - UNDER CONSTRUCTION!
http://www.wranglerforum.com/f330/2x...ad-490865.html
Old Jeep that was totaled (and SOLD!):
http://www.wranglerforum.com/f330/2x...ad-101879.html
'04 SV1000s:
http://www.svrider.com/forum/showthread.php?t=280873
2xs is offline   Quote Quick Reply
Old 01-13-2014, 05:47 PM   #20
Jeeper
 
screamingmeme322's Avatar
 
Join Date: Jan 2014
Location: Des Moines Iowa
Posts: 19
I will grab a volt meter and check everything out. Thanks so much. I will let everyone know what I find out.
__________________
Brandie Johnson
screamingmeme322 is offline   Quote Quick Reply
Old 01-13-2014, 05:56 PM   #21
jkp
Jeeper
 
Join Date: Mar 2010
Location: Warner Robins, GA
Posts: 409
It it's still throwing a TPS code, be sure the throttle body is clean.

The Idle Air Control valve can get dirty and stick causing idle problems.

Also, you can disconnect the battery to reset the codes to see if it comes back.
__________________
'92 Islander
'06 Rubicon
jkp is offline   Quote Quick Reply
Old 02-21-2014, 06:36 AM   #22
Jeeper
 
screamingmeme322's Avatar
 
Join Date: Jan 2014
Location: Des Moines Iowa
Posts: 19
Now that there has finally been a small "thaw" around here I crawled all over the engine and checked everything. After sitting and just staring at "Jed" (my Jeep), I decided to just go get another throttle positioning sensor and put that in. It worked!! I guess the first one I put in was bad. Go figure! Thanks so much for all the suggestions!!!

__________________
Brandie Johnson
screamingmeme322 is offline   Quote Quick Reply
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Jeep Wrangler Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools

Posting Rules
You may post new threads
You may 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
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Decoding Check Engine Light Gumpy2030 TJ General Discussion Forum 17 03-09-2011 10:46 PM
Check engine light the old guy TJ Tech Forum 3 11-25-2010 02:41 PM
Check Engine Light? Dewry636 TJ Tech Forum 0 10-29-2010 04:31 PM
check engine light? NEED HELP shorty8914446 TJ Tech Forum 4 03-08-2010 04:26 PM
check engine light? off road rescue TJ Tech Forum 1 03-14-2007 11:49 PM



» Network Links
»Jeep Parts
» Featured Product

All times are GMT -5. The time now is 12:47 AM.



Jeep®, Wrangler, Liberty, Wagoneer, Cherokee, and Grand Cherokee are copyrighted and trademarked to Chrysler Motors LLC.
Wranglerforum.com is not in any way associated with the Chrysler Motors LLC