94 2.5 in a 91 YJ....need help - Jeep Wrangler Forum
Jeep Wrangler Forum

Go Back   Jeep Wrangler Forum > YJ Jeep Wrangler Forum > YJ Tech Forum

Join Wrangler Forum Today


Reply
 
Thread Tools

Please support our sponsors and let them know you heard about them on WranglerForum.com
Old 03-30-2012, 05:58 PM   #1
Newb
 
Join Date: Dec 2010
Posts: 5
94 2.5 in a 91 YJ....need help

I posted a question about this before but really never got an answer. I have a 91 YJ that was originally a 2.5 5spd. the engine was replaced with a 94 2.5. It was running fine but just stopped (after 10k+ miles) after troubleshooting it, it turns out that it needs a computer. my problem is should I order the computer for a 1991 or a 1994 YJ? Or are they the same for certain years (like 1990 to 2012 *just using those years as an example I know it wouldnt be that big of a coverage period). I really need to know if somebody knows for certain what computer to use.
Thanks for the help. This is a great forum, lots of useful info on here!
Joe

jkleinjr is offline   Quote Quick Reply
Old 03-30-2012, 06:01 PM   #2
Jeeper
 
Xpress's Avatar
 
Join Date: Jan 2011
Location: El Cajon
Posts: 2,566
Order the ECM you need for your year Jeep. The 1991-1995 Jeeps share the same basic components and layout.

__________________


2.5L Genius of some sort.
Xpress is offline   Quote Quick Reply
Old 03-30-2012, 06:10 PM   #3
Jeeper
 
Join Date: Aug 2011
Location: Central Maine
Posts: 274
It depends on how it was swapped and it sounds like you didn't do it. They could have just swapped the block and re-used all the '91 components or it could be all '94.

I'd check to see if you still have a cable-drive speedo, if you do then buy a '91 PCM and only the '91. If the speedo is electric a '92 to '95 PCM should work fine. Make sure you get one for a 5-spd if that's what you're running.
brentd711 is offline   Quote Quick Reply
Old 03-30-2012, 06:58 PM   #4
Jeeper
 
Join Date: Nov 2011
Posts: 717
use what you had

You should be able to pull the numbers off the failed one and replace with the same part number?
ballistx is offline   Quote Quick Reply
Old 03-31-2012, 10:32 AM   #5
Jeeper
 
YJ325i's Avatar
 
Join Date: Mar 2012
Location: Denver
Posts: 401
Call the dealer and tell them your situation, sometimes newer ecm's have updates from previous years to solve known fuel management issues. Was your swap "complete"? intake and exhaust sensors and actuators? The ecm only manages intake and exhaust, not the engine itself. Oops, silly me I forgot about cam and crank signals. Are the tone rings different for those years?
YJ325i is offline   Quote Quick Reply
Old 03-31-2012, 02:01 PM   #6
Newb
 
Join Date: Dec 2010
Posts: 5
I didnt do the engine swap i bought the jeep with the 94 engine already in it. when they did the swap for whatever reason they didnt use just the block/head. They used all the components from the 94. I know this because when I needed a distributor pick-up the 91 and 94 are different distributors. I am having the problem (that seems to be discussed much on wrangler forums) with the intermittent no start/no CEL. It will at times crank until the battery dies other times it starts right up then I will drive it for awhile and it starts to die. It then gets to the point where it wont start/run at all. If I leave it sit for a few days it usually starts up again and the circle continues. I cant just use the computer thatsin it now 'cause when this originally happened(while I was out of state visiting my parents) the mechanic there put a used ECM in and it was ok for awhile but its back now. Its frustrating! Im almost to the point where I m goin to give up. I tried reading over the FAQ either on this site or jeepforums.com where it explains the steps to try and narrow down a short or the need for a new computer but I could only scratch my head and wonder at all the steps it was talking about. Im just going to replace the computer and hope that fixes it. Anybody have any other suggestions? Ive replaced the fuel pump, fuel pressure reg, starter, ignition switch, map sensor, dist pick-up, crank sensor, ASD sensor and camshaft sensor and still have the same trouble. ( all codes that were thrown by the computer at one time or another)
Joe

jkleinjr is offline   Quote Quick Reply
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Jeep Wrangler Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools

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 Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Looking to meet and wheel with fellow jeepers in so cali. Steven5113 On The Trail 1 04-01-2012 04:19 PM
Help with vacuum leak. JRIEDY85 TJ General Discussion Forum 2 03-31-2012 11:11 AM
need help with transfer case Blackjack93 YJ Tech Forum 3 03-30-2012 08:38 PM



» Network Links
»Jeep Parts
» Featured Product

All times are GMT -5. The time now is 04:38 AM.



Jeep®, Wrangler, Liberty, Wagoneer, Cherokee, and Grand Cherokee are copyrighted and trademarked to Chrysler Motors LLC.
Wranglerforum.com is not in any way associated with the Chrysler Motors LLC