Official 4.0 swap thread - Page 25 - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > Models > Jeep CJ Forum > Official 4.0 swap thread

Artec Holiday Sale!Bead Lock Wheels! Raceline, Trail Ready, & Trail-GearROCKRIDGE4WD Introduces a NEW Jeep Wrangler JK *led* tail

Reply
Unread 08-15-2013, 11:17 AM   #361
Gigemags05
Registered User
1980 CJ7 
 
Join Date: Oct 2012
Location: Denton, TX
Posts: 642
I spoke with the people at hesco and they suggested it might be the IAC valve so I changed it with no luck.

I reset the computer and its throwing
12
33
35
36
55

The only one that could really effect me is 35, which is:

35 Cooling fan relay circuit open or shorted
OR
35 idle switch motor fault - check connections

But I've checked all connections and they seem fine.

Should it be throwing codes 33 and 36 even though I have no ac or turbo?

The gentleman at hesco says he thinks I might have a bad pcm because its throwing codes that don't apply to my jeep. He said if I have a functioning speed sensor that my computer should learn. I assume my speed sensor is functioning. It's brand new. If it wasn't functioning would the speedometer still work?

Have any of you had issues with the original 4.0 pcm not working properly after the swap?

I just don't want to drop $400 on the hesco pcm if its not necessary.

Gigemags05 is offline   Reply With Quote Quick reply to this message
Unread 08-15-2013, 11:38 AM   #362
NelsonATC
Registered User
1980 CJ7 
 
Join Date: May 2009
Location: Warwick, RI
Posts: 423
35 is a cooling relay switch, which I don't have connected in mine either, as I have my own electric fan control wired up. This will show up when I pull codes on mine. This makes me think you're using some form of XJ harness/PCM, because the wranglers never had Electric fans.

33 shows up on mine as well, and I don't have ac. This shows up on most YJ and XJ's iI have pulled codes from, and many of them don't have air conditioning.

I've never seen 36 come up before, but I don't think that it's a problem. I classify that along with the air conditioning code that came up.

Even if you are not throwing a check engine light, there are still codes in the system if you check them. My jeep as it stands right now, is running fine, even though the above codes would show up if I decided to pull them.


How long is your jeep running before it dies? Is it running for a few seconds? A few minutes? Half an hour? At full operating temperature? When it's cold?

I'm typing this on my phone right now, so I can't look back through the thread to see if you've already answered it. If you have, I apologize for asking again.
__________________
Mike
1980 CJ7
NelsonATC is offline   Reply With Quote Quick reply to this message
Unread 08-15-2013, 11:54 AM   #363
Gigemags05
Registered User
1980 CJ7 
 
Join Date: Oct 2012
Location: Denton, TX
Posts: 642
Yes, my pcm is from a cherokee.

It'll run fine for a while then die. Sometimes before operating temp and sometimes after. It'll start right up again and might run for awhile or it might die again quickly.
Gigemags05 is offline   Reply With Quote Quick reply to this message
Unread 08-15-2013, 12:10 PM   #364
NelsonATC
Registered User
1980 CJ7 
 
Join Date: May 2009
Location: Warwick, RI
Posts: 423
Okay, that helps a little:


I had a similar problem about two months after my swap. I ended up tracing it back to the coolant temperature sensor. Once I replaced that, the problem went away. It's a cheap part, so it maybe worth a try.

If you do go the PCM route, there is no need to spend $400 to get the Hesco unit. I would find someone that sells used Jeep parts in your area, and see if they have one. I got mine for something like $40. For what it's worth, all of the "new" units out there are really rebuilt factory units, or so I am told.
__________________
Mike
1980 CJ7
NelsonATC is offline   Reply With Quote Quick reply to this message
Unread 08-15-2013, 01:02 PM   #365
Gigemags05
Registered User
1980 CJ7 
 
Join Date: Oct 2012
Location: Denton, TX
Posts: 642
You mean the sensor that the gauge plugs into on the back of the head?

Or the sensor in the thermostat housing?

I'll definitely give that a shot.

Can anyone direct me to a link or any info on checking the pickup tube/ fuel sock in the tank? Is it possible that its partly clogged?
Gigemags05 is offline   Reply With Quote Quick reply to this message
Unread 08-15-2013, 04:12 PM   #366
NelsonATC
Registered User
1980 CJ7 
 
Join Date: May 2009
Location: Warwick, RI
Posts: 423
Thermostat housing.
__________________
Mike
1980 CJ7
NelsonATC is offline   Reply With Quote Quick reply to this message
Unread 08-17-2013, 04:32 PM   #367
Gigemags05
Registered User
1980 CJ7 
 
Join Date: Oct 2012
Location: Denton, TX
Posts: 642
I replaced the coolant temp sensor with no luck.

I put a fuel pressure tester on it and its holding around 35-40 at all times, even when it's dying.

Is there any chance I have the cps gap too wide or too narrow?

I'm out of ideas on this thing.
Gigemags05 is offline   Reply With Quote Quick reply to this message
Unread 08-17-2013, 04:41 PM   #368
Skerr
<*////><
 
Skerr's Avatar
1985 CJ7 
 
Join Date: Sep 2008
Location: White Springs, Florida
Posts: 8,912
Quote:
Originally Posted by Gigemags05 View Post
I replaced the coolant temp sensor with no luck.

I put a fuel pressure tester on it and its holding around 35-40 at all times, even when it's dying.

Is there any chance I have the cps gap too wide or too narrow?

I'm out of ideas on this thing.
We just broke into the 4.0 world so I don't know much! If it is pointing to the CPS, could it be loose? We gapped ours with cardboard from a cereal box.
__________________
Kerrdog
Go Fish! <*////><

But the right word at the right time... "Hey, give me a little hug!" That's the difference between lightning and a harmless lightning bug!
Skerr is offline   Reply With Quote Quick reply to this message
Unread 08-17-2013, 04:48 PM   #369
Gigemags05
Registered User
1980 CJ7 
 
Join Date: Oct 2012
Location: Denton, TX
Posts: 642
It's on nice and tight. It starts up and runs fine so I'm doubting its the gap, just grasping for straws.
Gigemags05 is offline   Reply With Quote Quick reply to this message
Unread 08-17-2013, 04:56 PM   #370
Skerr
<*////><
 
Skerr's Avatar
1985 CJ7 
 
Join Date: Sep 2008
Location: White Springs, Florida
Posts: 8,912
Quote:
Originally Posted by Gigemags05 View Post
It's on nice and tight. It starts up and runs fine so I'm doubting its the gap, just grasping for straws.
And I am throwing them at you!! Good luck.
__________________
Kerrdog
Go Fish! <*////><

But the right word at the right time... "Hey, give me a little hug!" That's the difference between lightning and a harmless lightning bug!
Skerr is offline   Reply With Quote Quick reply to this message
Unread 09-15-2013, 09:20 PM   #371
sfeather11
Registered User
1982 CJ8 
 
Join Date: Sep 2013
Location: Landenberg, PA
Posts: 2
EGR or not?

Hi all, started this swap project about 6 years ago, then kids came along. Well, finally getting back into it and had a question. I've got my '95 head sitting on my '82 block. I re-used my 258 intake and am using the exhaust manifold from the 4.0. I am undecided on whether to use the Howell TBI kit or an MC2100 carb. Has anyone else with this intake/exhaust manifold setup hooked up their EGR? If so, what tube did you use? I cannot use my original since the 4.0 head is a little taller. Do I actually even need EGR? What would be the effects if I just plugged the holes?

Peace!
sfeather11 is offline   Reply With Quote Quick reply to this message
Unread 09-16-2013, 08:12 PM   #372
sfeather11
Registered User
1982 CJ8 
 
Join Date: Sep 2013
Location: Landenberg, PA
Posts: 2
Hi all, disregard the above post. After searching a bit I found an awesome thread about EGRs. After reading, I decided I will not be hooking it up, so the question is moot!

Peace!
sfeather11 is offline   Reply With Quote Quick reply to this message
Unread 12-24-2013, 09:33 AM   #373
captkhaos
Registered User
1980 CJ7 
 
Join Date: Oct 2009
Location: Ft. Lauderdale, FL
Posts: 167
Hello,
I've read every (well almost every) post of the 398 of them on this thread but have not found the answer I am looking for. Yes, I did a search. I have a 1980 CJ7 with a 258 and have a 4.0 head ready to go. The only thing stopping me is the exhaust header. I have had 3 engines in this Jeep during the 30 years I've owned it and had headers on all of them. Besides the cam, the header seems to make the most difference. I have found very little reference here about headers (or cams) but I don't want to start the swap until I have the right one... especially if I'm gonna pay $500 + for a Borla etc. Can anyone PLEASE give me some advice on a known working header for a 4.0 in a CJ7?

BTW, My 258 (4.2) runs great with a Crane RV cam, Crane ignition and a cheap Hooker header. The Carter BBD is a POS and the 258 really came alive with a Holley 350 cfm 2 bbl. Very easy install. The 4.0 head requires 390 cfm though so I went with a Weber 38/38. I'll consider TBI after I get it running with the new head. Trick Flow makes the 7/16" bushings for the head bolts. Expensive though. I'll look into the copper pipe idea. Thanks for all the help. Merry Christmas!! Dan
captkhaos is offline   Reply With Quote Quick reply to this message
Unread 12-24-2013, 09:41 AM   #374
billybooster2
Registered User
1983 CJ8 
 
Join Date: Jul 2008
Location: Cow Mountain, CA
Posts: 1,101
Quote:
Originally Posted by captkhaos View Post
Hello,
I've read every (well almost every) post of the 398 of them on this thread but have not found the answer I am looking for. Yes, I did a search. I have a 1980 CJ7 with a 258 and have a 4.0 head ready to go. The only thing stopping me is the exhaust header. I have had 3 engines in this Jeep during the 30 years I've owned it and had headers on all of them. Besides the cam, the header seems to make the most difference. I have found very little reference here about headers (or cams) but I don't want to start the swap until I have the right one... especially if I'm gonna pay $500 + for a Borla etc. Can anyone PLEASE give me some advice on a known working header for a 4.0 in a CJ7?

BTW, My 258 (4.2) runs great with a Crane RV cam, Crane ignition and a cheap Hooker header. The Carter BBD is a POS and the 258 really came alive with a Holley 350 cfm 2 bbl. Very easy install. The 4.0 head requires 390 cfm though so I went with a Weber 38/38. I'll consider TBI after I get it running with the new head. Trick Flow makes the 7/16" bushings for the head bolts. Expensive though. I'll look into the copper pipe idea. Thanks for all the help. Merry Christmas!! Dan

I went with this one from kospeed on ebay. Runs great, not Borla but less $$$ too! Have you upgraded the injectors to the '703' 4 hole pintle (Dodge Neon)?

http://www.ebay.com/itm/91-99-JEEP-G...item27c7e46838
billybooster2 is offline   Reply With Quote Quick reply to this message
Unread 12-24-2013, 09:43 AM   #375
Kman1983
Registered User
1983 CJ5 
 
Join Date: Aug 2008
Location: , Vermont
Posts: 353
I'm still running the stock 4.0 header on my CJ5. Welded the crack up years ago and it has been fine.
__________________
Rolled Red Jeep Club Member #258
'83 CJ5, 4.0 MPFI swap, T18/D20, CenterForce II clutch, Dana44/30(73 CJ5) with 3.73's,'79 knuckles and 11" discs, sagged 4" lift, 2" BL, 34x9.50x15 Super Swamper Pizza Cutters

My wifes website The Vermont JeepGirl http://www.vermontjeepgirl.com/

"Good Girls and Dirty Jeeps" a song by Opal Justice http://youtu.be/9xRtRE45OVQ
Kman1983 is offline   Reply With Quote Quick reply to this message
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.
Note: All free e-mails have been banned due to mis-use. (Yahoo, Gmail, Hotmail, etc.)
Don't have a non-free e-mail address? Click here for a solution: Manual Account Creation
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


Suggested Threads





Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.