Is this right for my fuel pressure? - JeepForum.com

 
LinkBack Thread Tools
post #1 of 8 Old 06-01-2009, 08:53 PM Thread Starter
bjl95mustang
Registered User
 
bjl95mustang's Avatar
1998 ZJ 
 
Join Date: Dec 2005
Location: Austin, Texas
Posts: 805
Is this right for my fuel pressure?

I checked my fuel pressure and the fsm says 49 +/- 2 psi. At idle my gauge is erratic and bounces between 45 and 55 psi. I rev it up and it's not as erratic but it still moves between 48-52 psi.

Should the pressure be steady? I can feel it pulsing through the gauge.


ZJ 98 5.2 LIMITED De-Badged

4.5" Lift: RE 4.5" springs,Iro rear 3.5 springs+1" spacer, RE shocks, All adjustable arms, IRO front track bar and HD bracket, Rear jks track bar, 1-Ton Steering, 242 tc, 33x12.5x15 GoodYear wrangler silent tires, 15" rock crawler rims, Aussie Locker For My 44A, 760X u-joint front axles.

Soon to come Lock Right Front Locker.

Jeep Inferno member #10

Texas Jeep Club Member #78
bjl95mustang is offline  
Sponsored Links
Advertisement
 
post #2 of 8 Old 06-01-2009, 09:12 PM
Mickey_D
Registered User
1997 ZJ 
 
Join Date: Aug 2008
Location: 40 3'42.36"N 112 2'16.73"W
Posts: 6,867
Fuel pressure is only checked with the ignition on, engine off. You will never get an accurate reading with the engine running.

1997 ZJ 5.2 Orvis, Baby!
1953 Willys M100 trailer Tagalong
________________
[_][][][][][][][][_]


Mickey_D is offline  
post #3 of 8 Old 06-01-2009, 09:16 PM
xJoshxx
Registered User
2012 WK 
 
Join Date: Sep 2008
Location: Burlington, Kentucky
Posts: 5,533
Quote:
Originally Posted by Mickey_D View Post
Fuel pressure is only checked with the ignition on, engine off. You will never get an accurate reading with the engine running.
x2 fuel pressure varies when running.

Sold4" Hybrid lift TeraFlex coils IRO Adjustable LA's Jks tracbar 1.25spidertrax spacers 265/75/16 Dura-tracs
Quote:
Originally Posted by moPowered View Post
The SRt-8's are a liberty design.
2011 WK2 ORA2 sold
2012 WK2 SRT8 - Current
99 WJ Limited Lifted.
2001 WJ stock 4.0 304k miles
xJoshxx is offline  
post #4 of 8 Old 06-01-2009, 09:18 PM Thread Starter
bjl95mustang
Registered User
 
bjl95mustang's Avatar
1998 ZJ 
 
Join Date: Dec 2005
Location: Austin, Texas
Posts: 805
The fsm says start the engine.

So it will move that much on a returnless system?

Back when I had my mustang I could dial in the pressure to an exact ammount.

ZJ 98 5.2 LIMITED De-Badged

4.5" Lift: RE 4.5" springs,Iro rear 3.5 springs+1" spacer, RE shocks, All adjustable arms, IRO front track bar and HD bracket, Rear jks track bar, 1-Ton Steering, 242 tc, 33x12.5x15 GoodYear wrangler silent tires, 15" rock crawler rims, Aussie Locker For My 44A, 760X u-joint front axles.

Soon to come Lock Right Front Locker.

Jeep Inferno member #10

Texas Jeep Club Member #78
bjl95mustang is offline  
post #5 of 8 Old 06-01-2009, 09:20 PM
Mickey_D
Registered User
1997 ZJ 
 
Join Date: Aug 2008
Location: 40 3'42.36"N 112 2'16.73"W
Posts: 6,867
Um, someone forgot to put the crack pipe down the day they wrote that page? :shrug:

Never have I heard of checking fuel pressure with it running. As a matter fact, on the Vortec engines the wildly fluctuating fuel pressure at idle can actually destroy a pressure gauge...


[EDIT] Ok, that is just too weird. I just looked at my 95 FSM and it says the same thing - 39psi with the engine at idle. How odd.

1997 ZJ 5.2 Orvis, Baby!
1953 Willys M100 trailer Tagalong
________________
[_][][][][][][][][_]



Last edited by Mickey_D; 06-01-2009 at 09:31 PM.
Mickey_D is offline  
post #6 of 8 Old 06-02-2009, 06:35 AM Thread Starter
bjl95mustang
Registered User
 
bjl95mustang's Avatar
1998 ZJ 
 
Join Date: Dec 2005
Location: Austin, Texas
Posts: 805
So can someone on here hookup a pressure gauge to thiers and tell me what it does while running?

ZJ 98 5.2 LIMITED De-Badged

4.5" Lift: RE 4.5" springs,Iro rear 3.5 springs+1" spacer, RE shocks, All adjustable arms, IRO front track bar and HD bracket, Rear jks track bar, 1-Ton Steering, 242 tc, 33x12.5x15 GoodYear wrangler silent tires, 15" rock crawler rims, Aussie Locker For My 44A, 760X u-joint front axles.

Soon to come Lock Right Front Locker.

Jeep Inferno member #10

Texas Jeep Club Member #78
bjl95mustang is offline  
post #7 of 8 Old 06-02-2009, 09:08 AM
Redrum_1
Registered User
2000 WJ 
 
Join Date: Nov 2008
Location: Indiana
Posts: 74
I had a fuel pressure gauge hooked up to mine and at idle it held steady at 44 lbs.

2013 Dodge Ram 1500 Express Quad Cab. 5.7L Hemi 6 speed automatic 3:55 gears LSD with 20 inch rubber
2000 Jeep Grand Cherokee Limited 4.0L
2003 Nissan 350Z Enthusiast Model 6 speed manual
2002 Audi A6 Avant Quattro 3.0L Auto
Redrum_1 is offline  
post #8 of 8 Old 06-02-2009, 06:14 PM Thread Starter
bjl95mustang
Registered User
 
bjl95mustang's Avatar
1998 ZJ 
 
Join Date: Dec 2005
Location: Austin, Texas
Posts: 805
Thats what I needed to know. I think the regulator is going out.

ZJ 98 5.2 LIMITED De-Badged

4.5" Lift: RE 4.5" springs,Iro rear 3.5 springs+1" spacer, RE shocks, All adjustable arms, IRO front track bar and HD bracket, Rear jks track bar, 1-Ton Steering, 242 tc, 33x12.5x15 GoodYear wrangler silent tires, 15" rock crawler rims, Aussie Locker For My 44A, 760X u-joint front axles.

Soon to come Lock Right Front Locker.

Jeep Inferno member #10

Texas Jeep Club Member #78
bjl95mustang is offline  
Reply

Quick Reply
Message:
Options

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:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.



Email Address:
OR

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.




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
What fuel pressure does my 5.2/318 need? sand zj ZJ Grand Cherokee Forum 8 09-02-2013 04:00 PM
No fuel pressure, Fuel Pump? CPS? ECU? Relay? 95cherokee33s ZJ Grand Cherokee Forum 2 10-22-2008 08:57 PM
What's my fuel pressure? wmm_16 ZJ Grand Cherokee Forum 4 09-07-2006 11:53 AM
Fuel pressure.. zvanit03ru ZJ Grand Cherokee Forum 4 06-12-2006 06:42 AM
No Fuel pressure JTDEG ZJ Grand Cherokee Forum 7 12-23-2004 05:00 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