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
  #1  
Old August 4th, 2006, 09:32
Biglead's Avatar
Biglead Biglead is offline
NAXJA Forum User
 
Join Date: May 2005
Location: Bay Area, California
Posts: 13
Question Fuel injection problems

For a project, I purchased an 89 pioneer with really high mileage with the intention of making it in to a trail rig. Anyway the 300,000+ mile engine was replaced with a rebuilt long block from the local parts store which is working fine but I used the original fuel injection parts from the old motor. The motor has been working great for the last 10k but now I am noticing a hiss coming from the injector closest to the firewall when I start the engine on colder mornings. There are no fluids leaking from the injector and I can wiggle it to make the hiss go away. I know I need to replace them or have them rebuilt because they are pretty old. BUT I recently read a few articles on replacing the old ones with certain year Ford or later year XJ injectors and increasing the mileage a bit over stock. Something about a better spray increasing mileage and what not. Since the injectors are pretty expensive to replace I was wondering if anyone else has used other than stock replacements with any noticed improvement or am I better getting the correct ones for my make/model.
Reply With Quote
  #2  
Old August 4th, 2006, 09:53
RichP's Avatar
RichP RichP is offline
NAXJA Forum User
 
Join Date: May 2002
Location: Effort, Pa
Posts: 15,606
Re: Fuel injection problems

I bought a set from fiveoh motor sports, replaced the stockers with them when the new jasper reman went in. Same milage...
Reply With Quote
  #3  
Old August 4th, 2006, 10:19
langer1's Avatar
langer1 langer1 is offline
NAXJA Forum User
 
Join Date: Jun 2005
Location: Mineral City,Ohio
Posts: 5,006
Re: Fuel injection problems

The hissing sound is a vacuum leak around the injector, not the injector.
You did replace the o-rings? One may have gotten nicked when you did.
Reply With Quote
  #4  
Old August 4th, 2006, 14:36
Saudade's Avatar
Saudade Saudade is offline
NAXJA Member
 
Join Date: May 2005
Location: SoCal
Posts: 2,158
Re: Fuel injection problems

What Langer said about the leak x2. Most likely the end that goes into the head.

I bought a set on eBay that were from a Mustang. Got a set of 8 for about $50. I haven't notice any real mileage improvement over the long term. My throttle response did seem to improve. But then, my old injectors were pretty dirty.
Reply With Quote
  #5  
Old August 7th, 2006, 18:18
90cherk 90cherk is offline
NAXJA Forum User
 
Join Date: Dec 2005
Location: Oregon
Posts: 39
Re: Fuel injection problems

From my experience when my injectors started leaking I replaced with a pulled (not new and much cheaper) Bosch set purchased from five-o motor. Ended up having to replace one of those that for some reason was sticking open. Anyway after some other engine work now my mileage has gone up about 1mpg based on my highway driving which is better than the mileage I got when it was brand new 16 1/2 years ago.
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
N20, Water Injection, & Fuel Cooling GoliathJeeper Jeep Street and Performance 4 April 27th, 2006 15:02
HELP!!!! fuel injection problems UrbnXj OEM Tech Discussion 5 April 10th, 2006 07:28
Aftermarket Fuel Injection Boatwrench Modified Tech Discussion 0 May 9th, 2005 20:18
F**king Fuel Injection!!!! :( olivedrabcj7 Modified Tech Discussion 18 February 4th, 2005 16:14
ford fuel injection???? Codeman Modified Tech Discussion 1 January 10th, 2004 20:47


All times are GMT -7. The time now is 13:28.


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