Consistent Idle problem, sputter @ idle-3000 - Jeep Wrangler Forum
Jeep Wrangler Forum

Go Back   Jeep Wrangler Forum > YJ Jeep Wrangler Forum > YJ General Discussion Forum

Join Wrangler Forum Today


Reply
 
Thread Tools

Please support our sponsors and let them know you heard about them on WranglerForum.com
Old 01-25-2006, 02:02 AM
Thread Starter
  #1
 
Join Date: Jan 2006
Posts: 2
Consistent Idle problem, sputter @ idle-3000

I have read through tons of threads trying to figure out this probelm.
PLEASE HELP ME!

I've got a 95 wrangler with 2.5l

sometimes/most of the time when I start my jeep, idle speed will start out @ around 1500rpm then slowly go down to about 700-900(i beleive, or whatever is normal) then after a very short period of time(20 seconds or so) the idle will start to drop, and after about 10 more seconds gets down so low it feels like the jeep is going to stall... the engine then revs up all of a sudden to about 1100rpm then the process starts all over again....

now during this low rpm idle/almost stall. i can give it gas and the engine revs up, but wants to VERY quickly drop back down, if I were to try and take off, I virtually have no power, and if I push down on the throttle the engine will backfire like crazy... to the point of it going through the throttle body.. the problem will go away for a second then come right back, it will even come back in the middle of acceleration. even if I drive around for a while... the only thing i noticed is that, if I try to get on the highway, or any suspened higher RPM drive, then come to a stop the problem goes away(usually, not all the time)

I have read numerous threads on the egr valve, but it is only in effect when the engine gets up to temp... right? would a bad seal between intake/exhaust ports cause this? I recently changed the manifold gasket due to exhaust leak...

the problem is so consistent @ idle that I want to think electrical... my check eng. light goes off, and I get the 21 code, for O2 sensor, would the O2 sensor cause this? .... this problem happens a lot but the check engine light isn't always on, it usually doesn't come on until i have driven around a while...

whippet14 is offline   Quote
Old 01-25-2006, 08:28 AM   #2
 
Join Date: Oct 2005
Posts: 145
It could be the O2 sensor, but I'm more inclined to think it's a sensor like idle air control or map, maybe throttle position.

naviathan is offline   Quote
Old 01-25-2006, 01:23 PM   #3
Jack Lives Here!!!

WF Supporting Member
 
1BLKJP's Avatar
 
Join Date: Apr 2005
Location: Phoenix, AZ
Posts: 7,760
It could be an O2 censor, but I wouldn't think it would be that drastic. I also don't think it has anything to do with the gasket you replaced, because it should hi rev all the time if you don't have that manifold sealed correctly.

I would think idle air control also.
__________________
Thanks,
Jack Hickman

President - Arizona Off-Highway Vehicle Coalition
Vice-President - ASA4WDC
Arizona Rock Rats
1BLKJP is offline   Quote
Sponsored Links
Advertisement
 
Old 01-25-2006, 02:30 PM
Thread Starter
  #4
 
Join Date: Jan 2006
Posts: 2
my only response is, how would tie into the backfiring issue, and the loss of power? I read that I can take off the throttle body to get to the IAC and clean it, so I will give it a shot...
whippet14 is offline   Quote
Old 01-25-2006, 06:05 PM   #5
 
Join Date: Jan 2006
Posts: 529
You could also try playing with the mechanical distributor advace and retard settings, new plug wires etc.
04moneypit is offline   Quote
Old 01-26-2006, 07:41 AM   #6
 
Join Date: Oct 2005
Posts: 145
If it's reading the air flow wrong and the engine is running lean it will "prefire" as opposed to running too rich and "postfire (backfire)". Check your plugs. Sooty and black/wet is rich, white is lean and a nice even tan is perfect. Mine runs lean constantly and I haven't been able to figure out why. It's so lean I get these white deposits on the plugs. It runs great though!

naviathan is offline   Quote
Reply

Thread Tools

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
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
4.2 carb problems stray YJ Tech Forum 25 10-27-2016 01:16 AM
Idle problem and MAP sensor ROLYAK TJ Tech Forum 15 05-23-2014 04:36 PM
check engine light came on and speedo stopped working @ the same time. eric TJ General Discussion Forum 14 10-14-2013 12:05 PM
4.2 rough idle and stalling problem truemainer150 YJ Tech Forum 9 04-12-2008 05:10 PM
Very Sad I bought a Lemon... Jahaira_JeepYJ89_fan YJ General Discussion Forum 19 07-13-2007 03:01 PM





All times are GMT -5. The time now is 12:04 PM.


Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.1
User Alert System provided by Advanced User Tagging v3.1.0 (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.

Jeep®, Wrangler, Liberty, Wagoneer, Cherokee, Gladiator, Mopar and Grand Cherokee are copyrighted and trademarked to FCA US LLC.
Wranglerforum.com is not in any way associated with FCA US LLC.