4.0L knocking in a jeep wrangler Sahara - Jeep Garage - Jeep Forum

Go Back   Jeep Garage - Jeep Forum > Jeep Technical Discussion > Troubleshooting/Problems Discussion

Join Jeep Garage Today
Reply
 
Thread Tools Display Modes
 
  #1  
Old 07-20-2016, 09:07 AM
Member
 
Join Date: Jul 2016
Posts: 5
Thanks: 3
Thanked 0 Times in 0 Posts
Rep Power: 194
jwhitt40920 is on a distinguished road
4.0L knocking in a jeep wrangler Sahara

Hey ya'll, I'm new to this. I have a knocking sound on the left side, bottom of motor if you are looking at it from front of vehicle. It gets louder the higher the rpms. It is a 97 model. Was wondering if anyone could help me with this.

Reply With Quote
Sponsored Links
Advertisement
 
  #2  
Old 07-20-2016, 09:32 AM
Governor's Avatar
Premium Member
My Jeep: 2011 3.6L WK2
 
Join Date: Apr 2016
Location: Alabama
Posts: 1,607
Thanks: 626
Thanked 278 Times in 261 Posts
Rep Power: 79414
Governor has a reputation beyond reputeGovernor has a reputation beyond reputeGovernor has a reputation beyond reputeGovernor has a reputation beyond reputeGovernor has a reputation beyond reputeGovernor has a reputation beyond reputeGovernor has a reputation beyond reputeGovernor has a reputation beyond reputeGovernor has a reputation beyond reputeGovernor has a reputation beyond reputeGovernor has a reputation beyond repute
Re: 4.0L knocking in a jeep wrangler Sahara

Knocking is bad. Possibly rod or main bearing. Best to tear it down before irreparable damage is done.
Reply With Quote
  #3  
Old 07-20-2016, 11:42 AM
Member
 
Join Date: Jul 2016
Posts: 5
Thanks: 3
Thanked 0 Times in 0 Posts
Rep Power: 194
jwhitt40920 is on a distinguished road
Re: 4.0L knocking in a jeep wrangler Sahara

You have to go through the oil pan to check this right?
Reply With Quote
  #4  
Old 07-20-2016, 12:28 PM
Governor's Avatar
Premium Member
My Jeep: 2011 3.6L WK2
 
Join Date: Apr 2016
Location: Alabama
Posts: 1,607
Thanks: 626
Thanked 278 Times in 261 Posts
Rep Power: 79414
Governor has a reputation beyond reputeGovernor has a reputation beyond reputeGovernor has a reputation beyond reputeGovernor has a reputation beyond reputeGovernor has a reputation beyond reputeGovernor has a reputation beyond reputeGovernor has a reputation beyond reputeGovernor has a reputation beyond reputeGovernor has a reputation beyond reputeGovernor has a reputation beyond reputeGovernor has a reputation beyond repute
Re: 4.0L knocking in a jeep wrangler Sahara

Quote:
Originally Posted by jwhitt40920 View Post
You have to go through the oil pan to check this right?
Yes
Reply With Quote
  #5  
Old 07-20-2016, 12:32 PM
Member
 
Join Date: Jul 2016
Posts: 5
Thanks: 3
Thanked 0 Times in 0 Posts
Rep Power: 194
jwhitt40920 is on a distinguished road
Re: 4.0L knocking in a jeep wrangler Sahara

If the noise is coming from the bottom of the engine, could it be a rod coming from the lifters?
Reply With Quote
  #6  
Old 07-20-2016, 01:10 PM
Governor's Avatar
Premium Member
My Jeep: 2011 3.6L WK2
 
Join Date: Apr 2016
Location: Alabama
Posts: 1,607
Thanks: 626
Thanked 278 Times in 261 Posts
Rep Power: 79414
Governor has a reputation beyond reputeGovernor has a reputation beyond reputeGovernor has a reputation beyond reputeGovernor has a reputation beyond reputeGovernor has a reputation beyond reputeGovernor has a reputation beyond reputeGovernor has a reputation beyond reputeGovernor has a reputation beyond reputeGovernor has a reputation beyond reputeGovernor has a reputation beyond reputeGovernor has a reputation beyond repute
Re: 4.0L knocking in a jeep wrangler Sahara

A pushrod would be more from middle to top of engine, camshaft to head. Is the engine missing or just knocking? Bent pushrod will prevent a valve from opening and closing completely which should cause some skipping. You can better isolate where the sound is coming from with a mechanics stethoscope: https://www.amazon.com/s/ref=nb_sb_n...cs+stethoscope

Bottom end is crankshaft and piston rods.
Reply With Quote
The Following User Says Thank You to Governor For This Useful Post:
  #7  
Old 07-20-2016, 01:14 PM
Diesel Dan's Avatar
Member
My Jeep: 2015 3.0L WK2
 
Join Date: May 2015
Location: Mi.
Posts: 136
Thanks: 5
Thanked 27 Times in 17 Posts
Rep Power: 15066
Diesel Dan has a reputation beyond reputeDiesel Dan has a reputation beyond reputeDiesel Dan has a reputation beyond reputeDiesel Dan has a reputation beyond reputeDiesel Dan has a reputation beyond reputeDiesel Dan has a reputation beyond reputeDiesel Dan has a reputation beyond reputeDiesel Dan has a reputation beyond reputeDiesel Dan has a reputation beyond reputeDiesel Dan has a reputation beyond reputeDiesel Dan has a reputation beyond repute
Re: 4.0L knocking in a jeep wrangler Sahara

An old trick to try is to pull each spark plug individually. If it is a rod, then you will hear a difference or no sound, because there will be no load on the piston/rod.
__________________
'15 GC Limited, Diesel, Adventure 2, Luxury 2, CD, Block Heater, Blue/Black.
Reply With Quote
The Following 2 Users Say Thank You to Diesel Dan For This Useful Post:
  #8  
Old 07-20-2016, 02:23 PM
Member
 
Join Date: Jul 2016
Posts: 5
Thanks: 3
Thanked 0 Times in 0 Posts
Rep Power: 194
jwhitt40920 is on a distinguished road
Re: 4.0L knocking in a jeep wrangler Sahara

Well, my engine light come on. I took it to get it diagnosed and the mechanic said it read multiple miss fire code but it never missed a beat while driving it
Reply With Quote
  #9  
Old 07-20-2016, 08:41 PM
Governor's Avatar
Premium Member
My Jeep: 2011 3.6L WK2
 
Join Date: Apr 2016
Location: Alabama
Posts: 1,607
Thanks: 626
Thanked 278 Times in 261 Posts
Rep Power: 79414
Governor has a reputation beyond reputeGovernor has a reputation beyond reputeGovernor has a reputation beyond reputeGovernor has a reputation beyond reputeGovernor has a reputation beyond reputeGovernor has a reputation beyond reputeGovernor has a reputation beyond reputeGovernor has a reputation beyond reputeGovernor has a reputation beyond reputeGovernor has a reputation beyond reputeGovernor has a reputation beyond repute
Re: 4.0L knocking in a jeep wrangler Sahara

Quote:
Originally Posted by jwhitt40920 View Post
Well, my engine light come on. I took it to get it diagnosed and the mechanic said it read multiple miss fire code but it never missed a beat while driving it
What did he think about the knocking noise?
Reply With Quote
  #10  
Old 07-20-2016, 09:35 PM
Member
 
Join Date: Jul 2016
Posts: 5
Thanks: 3
Thanked 0 Times in 0 Posts
Rep Power: 194
jwhitt40920 is on a distinguished road
Re: 4.0L knocking in a jeep wrangler Sahara

He told me that it sounded like I would be putting in a motor shortly. I bought it used and he said that they put aa new head on it. So I figured that they put the new head on and got rid of it.

---------- Post added at 01:35 AM ---------- Previous post was at 01:32 AM ----------

I will try to get a video and see if I can get it to where you can hear it.
Reply With Quote
Reply

Tags
jeep, wrangler

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
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Wrangler Unlimited Sahara :: 2015 Jeep Unlimited Sahara philbest Member Garage Discussions 0 12-27-2014 07:45 PM
How is the 2008 Jeep Wrangler unlimited Sahara off road stock? Jmilz08 Wrangler-YJ, TJ & JK 0 12-08-2011 09:22 PM

Powered by vBadvanced CMPS v3.2.3

All times are GMT -5. The time now is 04:40 PM.


Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Copyright 2012 - JeepGarage.Org
The Jeep Grand Cherokee Owners Community

JeepGarage.org is in no way associated with or endorsed by FCA US LLC. Chrysler, Dodge, Jeep, Ram, Mopar and SRT are registered trademarks of FCA US LLC.