1993 GC 4.0 I6 starting problem - JeepForum.com
LinkBack Thread Tools
post #1 of 1 Old 01-09-2011, 12:00 PM Thread Starter
Registered User
Join Date: Jan 2011
Location: Eagan
Posts: 1
1993 GC 4.0 I6 starting problem

Ok guys, I new to the forums and need some help. I have a 1993 GC with a 4.0 I6 that is very difficult starting. It needs to be cranked several times before starting. When it does start it does not act as if it is flooded, rather starved for fuel. Starting usually occurs after one or two cycles of the key switch.

What I've done:

- New fuel pressure regulator, and test correctly on the pressure test
- New Fuel filter
- Fuel pressure tested, running psi 31, idle psi 30 psi, max psi 39
(vacuum hose disconnected)
- All fuses and relays test correctly
- The Fuel pump seems to operate normally during starts, idle and normal
operation, meaning it turns on and seems to pump fuel normally
- Oh and no noticeable leaks

My questions:

The fuel pressure will fall to 0 in the fuel injection rail after 35 min, any
ideas on the causes??? I'm assuming this is causing a fuel starvation issue on start up an would explain the rough start issue.

- Possibly a failed schrader valve (valve-stem looking valve on the
fuel rails) causing a bleed down?

- A bad fuel pump?

- Is there a check valve I'm not seeing?

- A leaky injector?

Kingjere is offline  

fuel pressure , fuel pressure regulator , fuel pump , starting issue , starting problem

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

Similar Threads
Thread Thread Starter Jeep Forums Replies Last Post
1993 Jeep Grand Cherokee fuel leakdown problem. Jess1256 ZJ Grand Cherokee Forum 6 04-23-2015 12:44 AM
1993 Abs Problem Help! nprice24x ZJ Grand Cherokee Forum 3 07-15-2010 07:36 AM
1993 GC transmission engagement problem neelix6555 ZJ Grand Cherokee Forum 3 12-04-2008 08:18 PM
1993 Grand Cherokee died a few mins ago, whats the problem? arkman ZJ Grand Cherokee Forum 4 02-27-2003 07:47 AM
1993 Jeep G. Cherokee Paint Problem jeff_connors ZJ Grand Cherokee Forum 6 10-16-2002 04:56 PM

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