hard start - Jeep Wrangler Forum
Jeep Wrangler Forum

Go Back   Jeep Wrangler Forum > TJ Jeep Wrangler Forum > TJ Tech Forum

Join Wrangler Forum Today

Thread Tools

Please support our sponsors and let them know you heard about them on WranglerForum.com
Old 01-19-2010, 12:26 PM   #1
jeeplover38's Avatar
Join Date: Dec 2009
Location: Fargo
Posts: 18
hard start

Would the 02 sensor going out make my 99 tj 4.0 l start hard?

jeeplover38 is offline   Quote Quick Reply
Old 01-19-2010, 12:50 PM   #2
Knows a couple things...

WF Supporting Member
Jerry Bransford's Avatar
Join Date: Nov 2005
Location: Escondido, Calif.
Posts: 29,159
Images: 2
If it only takes a long time to start after it has been sitting around, like overnight, that's a leaky anti-drainback valve letting the fuel drain down out of the fuel rail that connects to the fuel injectors and back into the gas tank. The long start time is the amount of time it takes the fuel pump to get fuel back up to the fuel rail on top of the engine and thus to the fuel injectors.

The anti-drainback valve is located inside the fuel pressure regulator that is positioned on top of the fuel pump. The fuel pressure regulator with that valve inside can be purchased separately and can be found either at the dealer (usually) and often on eBay for less $$$. You do have to drop the fuel tank to replace it but that's not a big job.

When you have a choice, buy American.

Jerry Bransford is online now   Quote Quick Reply
Old 01-19-2010, 03:24 PM   #3
jeeplover38's Avatar
Join Date: Dec 2009
Location: Fargo
Posts: 18
thanks Jerry!
jeeplover38 is offline   Quote Quick Reply

Quick Reply

Register Now

In order to be able to post messages on the Jeep Wrangler Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Please enter a password for your user account. Note that passwords are case-sensitive.
Confirm Password:
Email Address
Please enter a valid email 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.

Thread Tools

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 Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
95 YJ Hard to Start 95YJ YJ Tech Forum 14 09-15-2011 09:05 PM
Hard start. Where to start looking? atf8611 YJ Tech Forum 15 12-20-2009 03:01 PM
4.0 Hard to start and bad miss when cold. Any suggestions? tracer012000 TJ Tech Forum 0 10-18-2009 06:07 PM
Dad's 1991 4.0L is hard to start cold. Covrace YJ Tech Forum 3 08-02-2009 09:28 AM
2.4L hard to start nayr TJ Tech Forum 4 03-23-2008 11:54 AM

» Network Links
»Jeep Parts
» Featured Product

All times are GMT -5. The time now is 12:27 AM.

Jeep®, Wrangler, Liberty, Wagoneer, Cherokee, and Grand Cherokee are copyrighted and trademarked to Chrysler Motors LLC.
Wranglerforum.com is not in any way associated with the Chrysler Motors LLC