Fuel Pressure Regulator (FPR) keeps changing, engine hard to start - JeepForum.com
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > Models > Jeep Wrangler Forums > YJ Wrangler Technical Forum > Fuel Pressure Regulator (FPR) keeps changing, engine hard to start

The Cure for your Tie Rod Roll!Steering and more from Ruffstuff!Introducing MONSTALINER™ UV Permanent DIY Roll On Bed Line

Unread 04-03-2010, 03:20 PM   #1
Registered User
1990 YJ Wrangler 
Join Date: Jan 2009
Location: Iowa
Posts: 162
Fuel Pressure Regulator (FPR) keeps changing, engine hard to start

I've been fighting getting engine running consistent. It is a 4.2L with Weber Carb, nuttered, and team rush mod.

I have plenty of power in the lower rpm range but it seems to stall out in the middle of the power band. Seems to run fine sometimes and others it feels like it's missing. Also, once it's warmed up it is hard to start (starts easy when it's cold, very hard when it's warm).

Checked timing and it was 8 deg. BTDC. When I checked that, I noticed my FPR was reading zero pressure though it was obviously getting fuel. It had said 3.5 last time I looked at it but not sure how long ago that was. Anyway, I adjusted it to 3.5 psi and ran around the block. No change in the way it drove. Let it sit for an hour and started it again: hard to start and FPR is down to 1 psi or so.

I could have multiple issues but could my FPR or Pressure Guage be bad? Any idea on the easy-cold-start but hard-warm-start?


Augy is offline   Reply With Quote Quick reply to this message

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.

Thread Tools

Suggested Threads

Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.