Jeep hard starting - Jeep Wrangler Forum
Jeep Wrangler Forum

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

Join Wrangler Forum Today


Reply
 
Thread Tools

Please support our sponsors and let them know you heard about them on WranglerForum.com
Old 09-20-2010, 12:45 PM   #1
Jeeper
 
Wallygator's Avatar
 
Join Date: Aug 2010
Location: Vernon BC
Posts: 1,237
Question Jeep hard starting

Not sure exactly whats going on. Sometimes the jeep will fire up after only cranking 3-4 times. Other times it'll crank for a long time and still wont fire up. Thought it was the new fuel pump faulty so had it replaced under warranty. Same problem. Seems like it mostly does it after it's been sitting for more than a few hours. But other times it can sit all nite and fire up good. Mostly seems to give problems in cooler weather. Any suggestions? New crankposition sensor and TPS also in the last couple months. All the connections under the hood have been cleaned and seem fine

Wallygator is offline   Quote Quick Reply
Old 09-20-2010, 12:50 PM   #2
Knows a couple things...

WF Supporting Member
 
Jerry Bransford's Avatar
 
Join Date: Nov 2005
Location: Escondido, Calif.
Posts: 32,025
Images: 2
When the fuel pump was replaced, was the fuel pressure regulator that sits on top of the fuel pump also replaced? The fuel pressure regulator contains a check valve that keeps fuel in the fuel rail next to the fuel injectors for a fast start.

Try this... try turning the ignition key to the On position 4-5 times to cycle the fuel pump enough so it can refill the fuel line if a leaky check valve has allowed it to drain back down into the fuel tank. If the engine starts up faster after doing that, something in the fuel system... check valve, fuel injector, etc. is leaking and allowing the gasoline that is supposed to stay put in the fuel rail for a fast start to instead drain out and return back to the fuel tank instead. The delay in starting is normally the amount of time it takes the fuel pump to get fuel back up to the fuel injectors again.

__________________
Remember that having a different opinion doesn't also require one to be a jerk when expressing it.

When you have a choice, buy American.

Jerry Bransford is offline   Quote Quick Reply
Old 09-20-2010, 05:35 PM   #3
Jeeper
 
teddywetts's Avatar
 
Join Date: Sep 2010
Posts: 21
Got the same thing happening with my 97 tj. It starts everytime, but its just hard starting.
teddywetts is offline   Quote Quick Reply
Old 09-20-2010, 06:27 PM   #4
Jeeper
 
Wallygator's Avatar
 
Join Date: Aug 2010
Location: Vernon BC
Posts: 1,237
The work was done by a shop and I'm not sure if they checked the regulator. I would think they would have when it came back after they replaced the fuel pump the first time for having this problem. I,ll have to see if I can get a fuel pressure tester and see what happens. The problem only showed up a week or so after the first pump. is it possible something got into the pressurre regulator and if so will a fuel system flush get it out?
Wallygator is offline   Quote Quick Reply
Old 09-20-2010, 06:34 PM   #5
Knows a couple things...

WF Supporting Member
 
Jerry Bransford's Avatar
 
Join Date: Nov 2005
Location: Escondido, Calif.
Posts: 32,025
Images: 2
Did you try the on-off-on key sequence I suggested above to see if you're having a fuel leak-down problem?
__________________
Remember that having a different opinion doesn't also require one to be a jerk when expressing it.

When you have a choice, buy American.

Jerry Bransford is offline   Quote Quick Reply
Old 09-20-2010, 06:43 PM   #6
Jeeper
 
Wallygator's Avatar
 
Join Date: Aug 2010
Location: Vernon BC
Posts: 1,237
Not yet. Thing is it doesn't do it every time. someone even went so far as to suggest that it could be battery related.
Wallygator is offline   Quote Quick Reply
Old 09-20-2010, 09:13 PM   #7
Newb
 
Country4x4Lady's Avatar
 
Join Date: Sep 2010
Location: The sticks
Posts: 7
My 97 TJ is doing the same thing! Be sure to post if you figure out what it is... please
Country4x4Lady is offline   Quote Quick Reply
Old 09-20-2010, 09:47 PM   #8
Jeeper
 
WolfInJeepsClothing's Avatar
 
Join Date: Aug 2010
Location: Canada
Posts: 38
Images: 7
My 97 TJ sounds like it has the same problem and and I also had it on a 4.0l Cherokee as well. I'm almost possitive it is the check valve/leakdown as was pointed out. I've never bothered to fix it since on the second start attempt it starts almost immediately. Hardly worth investing allot of money in repairs. But I will try the key on/off/on too.

Thanks
Wolf
__________________
Jeeps, mine is special just like everybody else's....
WolfInJeepsClothing is offline   Quote Quick Reply
Old 09-20-2010, 10:33 PM   #9
Jeeper
 
Kristavsmichigan's Avatar
 
Join Date: Aug 2010
Location: roseville
Posts: 112
Ya mine is doing this now. 1998 tj
I did what Jerry said awhile ago and it stops the cranking. Now usually I heard the part Jerry is talking about is almost like a sensor and it is a 100$ part to replace but shops won't do that they want to replace the whole fuel pump for a liability risk. which is why I don't get why they wouldn't have replaced this part with the fuel pump??
__________________
-[COLOR=Magenta] Krista @
Kristavsmichigan is offline   Quote Quick Reply
Old 09-21-2010, 09:03 AM   #10
Jeeper
 
teddywetts's Avatar
 
Join Date: Sep 2010
Posts: 21
I tried the on and off sequence and mine started right away... So basically i have a problem, but one that might not be worth fixing?
teddywetts is offline   Quote Quick Reply
Old 09-21-2010, 11:25 AM   #11
Jeeper
 
Wallygator's Avatar
 
Join Date: Aug 2010
Location: Vernon BC
Posts: 1,237
I finally got it to throw a code and it was P1282 which is a bad fuel pump relay. Put in a Bosch and hopefully that cures it. Will keep ya posted.
Wallygator is offline   Quote Quick Reply
Old 09-22-2010, 10:27 PM   #12
Jeeper
 
Wallygator's Avatar
 
Join Date: Aug 2010
Location: Vernon BC
Posts: 1,237
So far so good. Since putting in the new Bosch relay all the priblems have gone away. Gonna see if it's just a coincidence tho. But I was told by a mechanic to get rid of the Hella that was in there as they are nothing but junk.

Wallygator is offline   Quote Quick Reply
Reply

Quick Reply
Message:
Options

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:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

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
jeep wrangler 2002 hard starting problems jeeperson TJ General Discussion Forum 6 03-11-2012 09:25 PM
Jeep starts hard after siting. Help nmill TJ Tech Forum 0 09-15-2010 08:38 AM
Jeep WJ hard accelerating problem oujea General Jeep Discussion 0 05-02-2010 05:33 PM
Chryseler Announces Prices for 2010 Geoff@Bestop Off-Topic 13 08-20-2009 11:10 PM
History of the Jeep. George T. General Jeep Discussion 8 02-04-2009 01:03 AM



» Featured Product

All times are GMT -5. The time now is 04:29 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