YJ electrical issues and more! - JeepForum.com
LinkBack Thread Tools
post #1 of 9 Old 07-13-2021, 08:31 AM Thread Starter
Registered User
Join Date: Jul 2021
Posts: 8
YJ electrical issues and more!

So I just bought a a beater YJ with a 2.5 and a 5 speed for a project, mostly to run on the national forest roads and trails that are near my property. I do however want to register and be able to use the jeep around town. The initial problem was it wouldn't shut off and upon looking it over I found some serious wiring alterations. Rather than try to sort this mess out I grabbed a complete harness on eBay and plan to start over. The pic shows the ignition coil with a wire plugged into the coil (to energize the coil I assume) but the wire is hot with 12v all the time and was run from the fuel pump relay. I'm guessing the coil should be receiving power from the ICM. That led me to notice no wires coming out of the distributor and sure enough no pickup inside the distributor. Maybe thats why the kid said it ran really rough going downtime road! Anyway I need to find a good engine harness wiring diagram to sort this out and hopefully get this rig running better. Any suggestions appreciated.

Attached Images
waspp is offline  
Sponsored Links
post #2 of 9 Old 07-13-2021, 10:05 AM
Registered User
1993 YJ Wrangler 
Join Date: Mar 2021
Location: SoCal
Posts: 369
What year is it?
93YJ4FUN is offline  
post #3 of 9 Old 07-14-2021, 12:30 AM
Registered User
JOExFROMxNY's Avatar
1988 YJ Wrangler 
Join Date: Dec 2009
Location: Long Island, NY
Posts: 762
If its an '88, try these:
Attached Thumbnails
Engine wiring harnesses 2.5L 1988.jpg   Instrument panel harnesses 1988.jpg  
JOExFROMxNY is offline  
post #4 of 9 Old 07-14-2021, 07:27 AM Thread Starter
Registered User
Join Date: Jul 2021
Posts: 8
It's a 1990. Yes that would helpful joexfromxny...thanks
waspp is offline  
post #5 of 9 Old 07-14-2021, 08:15 AM
Registered User
jtec's Avatar
2014 JK Wrangler 
Join Date: Oct 2017
Posts: 10,557
get a OEM manual, you will want the wiring diagrams.
Often when the fuel pump relay is involved in 'rewire' there is a lack of understanding of PCM time out.
1990 = renix. google 'cruiser54' a forum member and your new friend.

When I see the price of OEM I think aftermarket.
When I see the quality of aftermarket I think OEM.
jtec is online now  
post #6 of 9 Old 07-14-2021, 10:41 PM
Registered User
1990 YJ Wrangler 
Join Date: Mar 2021
Posts: 178
A member here has the FSM and the Electrical manual in .pdf to download from their signature. Hopefully someone will supply their name to help you. Sorry, Ive slept since I DL'ed it and dont remember who it is.
SevenSlotAddict is offline  
post #7 of 9 Old 07-15-2021, 09:51 PM
Registered User
1994 YJ Wrangler 
Join Date: Aug 2017
Location: San Diego
Posts: 178
xpage is offline  
post #8 of 9 Old 07-16-2021, 04:31 PM Thread Starter
Registered User
Join Date: Jul 2021
Posts: 8
Thanks much! I was able to find an article on 4wd mechanics that went over the way the tbi and electronic ignition system operates on the 2.5. The distributor has no pulse ring or pickup the advanced or retard is all done through the ecm and icm. I picked up an unmolested wiring harness so I hope I will be able to work through it and check the engine management sensors as I go.
waspp is offline  
post #9 of 9 Old 07-26-2021, 01:29 PM
Bikini Bridge Inspector
laybackman's Avatar
2010 JK Wrangler 
Join Date: Dec 2002
Location: Massachusetts
Posts: 7,370
Looks like xpage posted it before I did!

Do you know what was good about the good old days? I wasn't good, And I wasn't old!

Found out Grandpa is addicted to Viagra. No one is taking it harder than Grandma...
laybackman 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

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