Burning gas, bucking & serging - JeepForum.com
LinkBack Thread Tools
post #1 of 4 Old 05-15-2019, 03:47 PM Thread Starter
Registered User
Join Date: Jan 2013
Location: Fort Worth
Posts: 4
Burning gas, bucking & serging

2000 Grand Cherokee Laredo
Started out with a backfire & black soot on the ground & tail pipe. From that moment, I burned through a tank of gas every 2 days. It wasn't doing anything else except for a very rare hiccup (buck) while driving.
Replaced the coil pack, spark plugs & pcv valve & hose. The valve only because it basically crumbled apart and had to be placed.
Since that ^^^^^ it is not burning through gas anymore but now it shakes & rattles, vibrates, idles poorly and has no get up & go power. Once I do get to 60-70 mph, if the cruise is on it has big power surges. Engines kicks in & rpms race up to 4+. Takes a good 20 sec for it to kick in to gear and level out again unless I turn the cruise off.
Am I looking at fuel injectors now or, before I spend that amount of money, could it possibly be something else??

KellyannD is offline  
Sponsored Links
post #2 of 4 Old 05-15-2019, 06:48 PM
leadsled jeep
Registered User
leadsled jeep's Avatar
2002 WJ 
Join Date: Sep 2006
Location: TriCities
Posts: 1,752
With running conditions like those there should be some error codes I’d think. O2 codes maybe large vacuum leak.

'02 4.7HO ~222k ml. 2.5" BDS Springs, All new control arms and Addco Sways. 245-70-17.
leadsled jeep is offline  
post #3 of 4 Old 05-15-2019, 08:54 PM
Web Wheeler
Mattyjm's Avatar
2004 WJ 
Join Date: Dec 2014
Location: Butler, PA
Posts: 2,269
I'd think PCM or Throttle Position Sensor along with Idle Air Control Valve.

2004 Special Edition WJ. LOADED!
2004 Rocky Mountain Edition. Froggy Bandit. Wife's Daily Driver. PRISTINE! Stock height and may stay that way.....
Mattyjm is offline  
post #4 of 4 Old 05-16-2019, 01:14 PM
Registered User
1936 CJ2A 
Join Date: Feb 2016
Location: Los Angeles
Posts: 751
Clean or replace the idle air sensor and check for codes for the crank position sensor.
grayWJ4x4 is offline  

Quick Reply

Register Now

In order to be able to post messages on the JeepForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.

Email Address:


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page

Similar Threads
Thread Thread Starter Jeep Forums Replies Last Post
2002 Jeep Liberty 3.7L engine only starts with gas and shuts off if i let go of gas. Ap23242324 KJ Liberty Forum 11 11-28-2019 09:20 PM
My goal is to get 25+ mpg from my 99 XJ with 30 x 9.5 R15 ATs Charley3 XJ Cherokee Technical Forum 3864 10-19-2019 10:58 PM
TJ running rough gas stinks bad, bogging down at times and back firing mgaither0 TJ Wrangler Technical Forum 15 06-23-2019 11:45 AM
gas tank leak Kristian_Burns TJ Wrangler Technical Forum 5 06-14-2018 06:01 AM
Pure Gas in Denver Area txdutt JK Wrangler Technical Forum 2 04-20-2018 09:00 AM

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 On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome