1986 comanche. Rough idle, could it be the fuel injector? - JeepForum.com

LinkBack Thread Tools
post #1 of 3 Old 01-22-2013, 12:52 PM Thread Starter
Registered User
Join Date: Jul 2012
Posts: 7
Recently I've began to try and solve the issue of my comanche's rough idle. It has the 2.5l in it. Im getting about 15-16 mpg in. I know jeep isn't known for good fuel economy... But that low for a 4 banger?! I had a major vacuum leak at the bottom of the TBI where the block connects the 4 lines. I took the block out and fitted about 2 inches pieces of vacuum line for all 4 lines and voila, no more leak. I took it out to do some errands it still has somewhat of a rough idle. It definitely helped but when the truck is on and not moving the idle runs up and down in RPMs. Someone I work with told me the fuel injector could be clogged and said they should make a cone like spray onto the butterfly valve in the throttle body. When I checked mine it just sprays it in an unorganized burst onto the valve. Could I possibly need a new injector? I bought a refurb one 2 years ago to get the truck itself running because it didn't have one at all. But those 2.5 injectors are fairly expensive. I want to see what other simple things it could be before I fork over 125 bucks for one.

Last edited by colinkx250f; 01-22-2013 at 01:02 PM.
colinkx250f is offline  
Sponsored Links
post #2 of 3 Old 01-23-2013, 06:43 AM
Web Wheeler
cruiser54's Avatar
1990 MJ Comanche 
Join Date: Oct 2009
Location: Prescott
Posts: 11,191
Intake manifold bolts tight?

BG44K in the fuel tank to clean that injector.

If you own a Renix Jeep, you'll want to check this out.

An index to over 30 write-ups can be found in the link below


My Jeep Technical Photos

cruiser54 is offline  
post #3 of 3 Old 01-23-2013, 08:27 AM Thread Starter
Registered User
Join Date: Jul 2012
Posts: 7
Intake manifold is tightened down. I had to put a gasket in for it about a month ago
colinkx250f 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:


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.

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