Jumped Timing?? - '95 XJ 4.0 - JeepForum.com
 4Likes
  • 1 Post By bamaham
  • 1 Post By cruiser54
  • 1 Post By CJ7-Tim
  • 1 Post By 75SV1
 
LinkBack Thread Tools
post #1 of 8 Old 09-15-2019, 07:24 PM Thread Starter
bamaham
Registered User
 
Join Date: Apr 2019
Posts: 16
Xj Jumped Timing?? - '95 XJ 4.0

My daughter has a 95 Cherokee Country that started having problems last month. On her way home from work in high temperatures outside, the Jeep (affectionately named Walter by her sister), sprung a radiator leak and went dead about 1 mile from home. It went dead - she cranked back up, but it was running rough and she made it. I replaced radiator, water hoses and thermostat. I tried to crank and it was idling rough - like not firing on all cylinders. I checked plugs and used a scope to check out cylinders. All were good. Spark plug gap was good and plugs were clean.

The only thing I found that could be an issue was a plug wire on cylinder 6, so I replaced all plug wires just to be sure (they were only a couple of months old). I cranked it up and it started running rough, backfiring a bit and smelled to be running a bit rich. Would not idle on its own. I don't have tools to check compression.

I would not eve rate as a shade tree mechanic, I'm just not afraid of basic repairs. Could it have jumped timing?

downs likes this.
bamaham is offline  
Sponsored Links
Advertisement
 
post #2 of 8 Old 09-16-2019, 06:58 AM
cruiser54
Web Wheeler
 
cruiser54's Avatar
1990 MJ Comanche 
 
Join Date: Oct 2009
Location: Prescott
Posts: 12,006
She probably cooked the motor to be honest.
downs likes this.

If you own a Renix Jeep, you must check this out:


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


My Jeep technical photos:


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
cruiser54 is offline  
post #3 of 8 Old 09-16-2019, 07:19 AM
jtec
Registered User
 
jtec's Avatar
2014 JK Wrangler 
 
Join Date: Oct 2017
Posts: 6,490
keep cruiser comments in mind as we look at this, I am a hopeless optimist.
First I would not worry about it jumping time.

Ok the coolant is now full, the oil was checked and was not milkshake in appearance.
Engine starts - but idles poorly is the concern right now?
Did you disconnect the battery - (my guess) as a jeep has a relearn .
advise -
Before we tear into this - compression, coolant pressure testing, cap, rotor, eng sprayed coolant everywhere... lets let it relearn, google forum for tips.

When I see the price of OEM I think aftermarket.
When I see the quality of aftermarket I think OEM.
jtec is offline  
 
post #4 of 8 Old 09-16-2019, 08:11 AM
CJ7-Tim
Real Jeeps have dents
 
CJ7-Tim's Avatar
2000 XJ Cherokee 
 
Join Date: Apr 2002
Location: out in the garage - Minneapolis
Posts: 27,553
Quote:
Originally Posted by jtec View Post
First I would not worry about it jumping time.

……….. eng sprayed coolant everywhere...
I agree with jtec, start with the basics.


Buy a spray can of electrical contact cleaner. Disconnect and clean every engine sensor plug under the hood, and inside the distributor cap as well.

The Throttle Position Sensor hates water of any type, and can be damaged by excessive water intrusion. A faulty TPS or other sensor data distorted by water induced short circuits can cause the symptoms described.
bamaham likes this.

.

A recent Gallup public opinion poll shows the NRA, at 58% approval, has a higher approval rating than either Hillary Clinton or Barack Obama.

Progressive Liberalism: Bringing you new Healthcare ideas so wonderful, they have to include mandatory participation ...

Originally Posted by Ronald W. Reagan: Government is not the solution to our problems; Government is the problem.
CJ7-Tim is offline  
post #5 of 8 Old 09-16-2019, 09:02 AM
downs
Member
 
downs's Avatar
1995 XJ Cherokee 
 
Join Date: Oct 2018
Location: Hunt County
Posts: 479
Garage
If she drove it till it died after springing the coolant leak that greatly increases the chances the engine is toast, that means she probably seized the engine. You really need to do a compression check. The gauge is cheap and the test is easy. 20 dollars on Amazon for a gauge on Prime. Have it in a day or two. You can even rent them from nearly any autoparts store.

1995 Jeep Cherokee Country 4X4 Stock
AW4/NP231/C8.25/D30/"UpCounty" suspension
downs is offline  
post #6 of 8 Old 09-16-2019, 11:34 AM
75SV1
Registered User
 
Join Date: Sep 2003
Posts: 1,946
Is it sucking or losing coolant still? If so, then its probably warped the head. If not, I'd still do a radiator pressure test and compression test on the cylinders. Might also look at the cap and rotor. If moister got underneath there, it could have damaged some of the post.
bamaham likes this.
75SV1 is offline  
post #7 of 8 Old 10-06-2019, 09:23 PM Thread Starter
bamaham
Registered User
 
Join Date: Apr 2019
Posts: 16
Thanks for ll the suggestions. Unfortunately I have been swamped with too many other issues to even do anything since replacing radiator, cap and plug wire.

It fires up, just runs like crap. No visible coolant leaks anymore. Oil looks good. Old coolant did not look contaminated by oil.

This week I hope to have time to check engine codes like others suggested and then I am going to pull the valve cover off to take a look at things. I scoped the pistons with a small camera scope and did not see any damage.

Thanks for the help. I'll post what I find.
bamaham is offline  
post #8 of 8 Old 10-08-2019, 08:59 AM
Saudade
Registered User
1988 XJ Cherokee 
 
Join Date: Jun 2008
Location: SoCal
Posts: 1,480
Perhaps one cyl is *not* firing. To check, start engine, let idle. Then pull the fuel injector connector off #1. Does the idle drop further? Put it back on. Did the idle pick up?

Repeat with #2-6, one at a time. If you come across one cyl where the idle does not change, you found your bad boy. If they all drop, your problem is not specific to a particular cyl.

As others have said pressure test, and compression test.
Saudade is offline  
Reply

Quick Reply
Message:
Options

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

Password:


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



Email Address:
OR

Log-in











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



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