NAXJA Forums -::- North American XJ Association  

Go Back   NAXJA Forums -::- North American XJ Association > NAXJA Unibody Jeep Technical Forums > Jeep Cherokee XJ (1984 - 2001) > OEM Tech Discussion
HOME Member FAQ Sponsor Info Rules Bylaws E-Mail

OEM Tech Discussion Forum for OEM (Original Equipment) or stock XJs and MJs.

Reply
 
Thread Tools Display Modes
  #31  
Old January 31st, 2016, 04:36
SeanMR SeanMR is offline
NAXJA Forum User
 
Join Date: Jan 2016
Location: U.K.
Posts: 1
Re: 1996 XJ fuel pump and pressure regulator repair details

Hi all,

New to this site and this thread is very relative to what I'm trying to achieve at the moment. Has anyone had any headway with the getting the fuel guage to respond correctly?

Thanks

Sean
Reply With Quote
  #32  
Old July 19th, 2016, 22:44
McLovin83 McLovin83 is offline
NAXJA Forum User
 
Join Date: Oct 2014
Location: Oklahoma
Posts: 17
Re: 1996 XJ fuel pump and pressure regulator repair details

Just wanted to add to this.

I found this post:

http://www.justanswer.com/jeep/6l6fl...kee-needs.html

and the helpful mechanic listed a part number of 68001830AA for the sending unit. Looks like you can find the mopar version of this part and it isn't very expensive. Someone better off than me in terms of funds want to bite the bullet as buy one? You know, for science!
Reply With Quote
  #33  
Old July 23rd, 2016, 07:53
Anak's Avatar
Anak Anak is offline
Stranger
 
Join Date: Sep 2013
Location: In a strange land
Posts: 3,348
Re: 1996 XJ fuel pump and pressure regulator repair details

I was curious, and decided to make the $30 contribution to science.

What you get is the approximately 1" x 2" wafer that the fuel arm sweeps across. It certainly isn't going to help anybody who has a fuel delivery problem unless they can't keep track of when their tank is full or empty.

That said, it does pose some questions for me, particularly about the possibility of modifying a '97+ or ZJ tank and sending unit for use in the '96. Those units will fit, but pose a problem with the fuel gauge. To my knowledge no one has managed to figure out how to get them to talk with the '96 and down fuel gauge.

Now I just need to get my hands on a late model fuel pump/sending unit module and see what it would take to modify that. This little wafer might be the key to success.
__________________
Project "Scope Creep": 1996 4wd 4.0L, AX15
....

Baby it's cold outside.
Reply With Quote
  #34  
Old July 24th, 2016, 19:47
Anak's Avatar
Anak Anak is offline
Stranger
 
Join Date: Sep 2013
Location: In a strange land
Posts: 3,348
Re: 1996 XJ fuel pump and pressure regulator repair details

Here is what you get if you order that $30 fuel sending unit:



Note that is the actual piece in the lower right hand corner. For the sake of scale, instructions are printed on a standard 8 1/2" x 11" sheet of paper. I simply placed the "sending unit" and the sheet of paper on the scanner.

There is my contribution to science for the year.
__________________
Project "Scope Creep": 1996 4wd 4.0L, AX15
....

Baby it's cold outside.
Reply With Quote
  #35  
Old July 25th, 2016, 09:24
gradon's Avatar
gradon gradon is offline
NAXJA Forum User
 
Join Date: May 2006
Location: DC
Posts: 3,115
1996 XJ fuel pump and pressure regulator repair details

I just measured the 96's fuel sender resistance: 1.1K ohms empty to 100 ohms full.



Sent from my iPhone using Tapatalk
Reply With Quote
  #36  
Old July 27th, 2016, 09:52
McLovin83 McLovin83 is offline
NAXJA Forum User
 
Join Date: Oct 2014
Location: Oklahoma
Posts: 17
Re: 1996 XJ fuel pump and pressure regulator repair details

Quote:
Originally Posted by Anak View Post
Here is what you get if you order that $30 fuel sending unit:



Note that is the actual piece in the lower right hand corner. For the sake of scale, instructions are printed on a standard 8 1/2" x 11" sheet of paper. I simply placed the "sending unit" and the sheet of paper on the scanner.

There is my contribution to science for the year.


You are the freaking BOMB! Pretty much any time I've had a question about my 96, you've pretty much had a thread on it LOL!

I feel like we should start a 96 XJ owner thread so we can compile a list of our findings all in one spot!

Sorry for the thread derail and thank you for your contribution to SCIENCE!
Reply With Quote
  #37  
Old July 28th, 2016, 19:40
Anak's Avatar
Anak Anak is offline
Stranger
 
Join Date: Sep 2013
Location: In a strange land
Posts: 3,348
Re: 1996 XJ fuel pump and pressure regulator repair details



You are quite welcome.

I figure the '96s get a bad rap because they are unique and idiosyncratic.

For better or worse the same attributes apply to me.

I have to do my part just as a matter of self-interest.

__________________
Project "Scope Creep": 1996 4wd 4.0L, AX15
....

Baby it's cold outside.
Reply With Quote
  #38  
Old July 28th, 2016, 19:46
Anak's Avatar
Anak Anak is offline
Stranger
 
Join Date: Sep 2013
Location: In a strange land
Posts: 3,348
Re: 1996 XJ fuel pump and pressure regulator repair details

Geoff added some useful info over in Modified Tech that might be worthwhile to someone else perusing this thread:

Quote:
Originally Posted by GSequoia View Post
1987 - 1990 XJ
Empty 1 ohm
1/2 44 ohm
Full 88 ohmSource: 1989 FSM

1991 - 1996 XJ

Empty 105 ohm
1/2 33 ohm
Full 5 ohm
Source: 1993, 1995, 1996 FSM.

1997 - 2001 XJ
Float down 270 ohm
Float up 20 ohm
Note: This may not be the actual full and empty positions. The 1997 - 2001 FSMs do not lay the resistance values out the same as the earlier ones.
Source: 1999, 2000, 2001 FSM

ZJ

The only ZJ book I have is 1993:
Empty 105 ohm
1/2 32.5 ohm
Full 5 ohm
ZJ tanks seem to be an easy swap, and if the sending unit speaks the same language that may be a lifesaver for someone who can't come up with the right parts to keep their '96 fuel system operational.

And yes, I know it is a modification, but I think it is relevant to this thread.

Relevant Modified Tech thread: http://www.naxja.org/forum/showthread.php?t=1123236
__________________
Project "Scope Creep": 1996 4wd 4.0L, AX15
....

Baby it's cold outside.
Reply With Quote
  #39  
Old July 29th, 2016, 18:59
gradon's Avatar
gradon gradon is offline
NAXJA Forum User
 
Join Date: May 2006
Location: DC
Posts: 3,115
1996 XJ fuel pump and pressure regulator repair details

Yes, apparently I measured wrong, so disregard the resistance values I measured(already said that in other thread).


Sent from my iPhone using Tapatalk
Reply With Quote
  #40  
Old August 2nd, 2016, 21:38
ab56452001 ab56452001 is offline
NAXJA Forum User
 
Join Date: Jul 2016
Location: Australia
Posts: 20
Re: 1996 XJ fuel pump and pressure regulator repair details

Hi , just on the fuel pump , discovered today that my Alternator sometimes drops under 12 volts , I think this could be the reason for my Jeep's , surging/cutting out , what would be minimum volts to keep the pump running ? , cheers.
Reply With Quote
  #41  
Old August 3rd, 2016, 04:08
ab56452001 ab56452001 is offline
NAXJA Forum User
 
Join Date: Jul 2016
Location: Australia
Posts: 20
Re: 1996 XJ fuel pump and pressure regulator repair details

Seen an example today , at around 13 volts pump put out 50psi at 11volts 30psi , I think this could be my problem.
Reply With Quote
  #42  
Old August 9th, 2016, 08:04
Anak's Avatar
Anak Anak is offline
Stranger
 
Join Date: Sep 2013
Location: In a strange land
Posts: 3,348
Re: 1996 XJ fuel pump and pressure regulator repair details

From another thread, fuel pump/sending unit pinout:

Quote:
Originally Posted by Wayne Sihler View Post
from FSM 96.
6 cavities
#1-relay output(power?) DG/rd tracer
#2-sensor ground Bk/Lb
#3-Fuel level sensor DB
#4 open
#5-low fuel sensor Db/wt
#6-Ground BK
plug
6-5-4
3-2-1

Could be useful for diagnostic purposes.
__________________
Project "Scope Creep": 1996 4wd 4.0L, AX15
....

Baby it's cold outside.
Reply With Quote
  #43  
Old October 16th, 2016, 12:10
pstanstill pstanstill is offline
NAXJA Forum User
 
Join Date: Oct 2016
Location: tallahassee
Posts: 3
Re: 1996 XJ fuel pump and pressure regulator repair details

great thread, a lot of info in one place. I'm trying to help the mechanic in tampa who "fixed " my daughters 96. Fuel pump and regulator were replaced but pressure leaks down quickly. It runs fine once started but takes several key turns to prime up. I dont know if tank o-ring was replaced, also wondering about that flat rubber washer that didnt come with your new regulator. What else could be causing loss of pressure ( assuming new pump and regulator were installed properly.
Reply With Quote
  #44  
Old October 16th, 2016, 19:40
Anak's Avatar
Anak Anak is offline
Stranger
 
Join Date: Sep 2013
Location: In a strange land
Posts: 3,348
Re: 1996 XJ fuel pump and pressure regulator repair details

You could lose pressure at the engine end. A leaky injector (or two) could cause that, but I doubt it would take multiple efforts at priming in order to overcome that.

A leak external to the system (fuel line leak, fuel filter leak) should be easily identified by your nose.

That leaves us with a leak in the tank itself. A bad hose or a bad connection on a hose would be one failure mode. A defective check valve in either the new regulator and/or pump would be another mode (From what I have read both of those are supposed to have check valves, but it would seem both would have to be bad in order for this problem to occur. Not having dissected either I can't say with certainty whether they both do or not.).

If it were me I would drive it down to a quarter tank or so and then pull the assembly back out and check for issues with the hoses on the inside. If those all look good I would then get another regulator and try that. Another pump would be the last resort option.

Dealing with a shop is another matter entirely. While they should have the advantage of experience, I am consistently disappointed in the level of attention to detail. It is a rare thing anymore that I let any shop touch my vehicles. Best of luck.
__________________
Project "Scope Creep": 1996 4wd 4.0L, AX15
....

Baby it's cold outside.
Reply With Quote
  #45  
Old October 17th, 2016, 02:53
pstanstill pstanstill is offline
NAXJA Forum User
 
Join Date: Oct 2016
Location: tallahassee
Posts: 3
Re: 1996 XJ fuel pump and pressure regulator repair details

Thanks,anak. my daughter had to take the car back to school so I will have to encourage the shop- as best I can. To clarify my limited understanding of fuel pressure, the pump only pressurizes the fuel line, not the tank itself?A pinhole leak in the tank or the tank o-ring shouldnt matter?
Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Fuel Pressure Regulator Inklover17 OEM Tech Discussion 4 October 11th, 2008 10:29
fuel pressure regulator? arkansasduck OEM Tech Discussion 4 September 19th, 2006 13:53
stupid fuel pump... (or ghetto fuel pump repair) philip_g OEM Tech Discussion 27 July 19th, 2006 02:44
Fuel pressure regulator? Nick OEM Tech Discussion 7 May 14th, 2005 16:08
Fuel Pressure regulator asatxj OEM Tech Discussion 0 August 12th, 2003 05:58


All times are GMT -7. The time now is 08:56.


Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
NAXJA and NAXJA logo's Copyright NAXJA. All content/images Copyright NAXJA 1999-2014