98 ZJ Do I need a new Fuel Pump - JeepForum.com
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Unread 09-20-2009, 10:10 AM   #1
Registered User
1998 ZJ 
Join Date: Apr 2007
Location: Tucson AZ
Posts: 107
98 ZJ Do I need a new Fuel Pump

Hi Guys,

I think I need a new fuel pump but I thought I would check here first. The problem is when its been sitting for a while it takes alot longer then normal to start. I bought a Fuel pressure meter and these are the readings I got:

Normal pressure when Its been running is about 42psi
Cold pressure first thing in the morning 22psi
Cold pressure if I turn the key on then off without starting then on again is 42psi

When I did the key on and off then on again I was able to start straight away.

I also just replaced the PCM for another issue.




purple_jeep is offline   Reply With Quote
Unread 09-24-2009, 07:01 PM   #2
Registered User
1994 ZJ 
Join Date: Jul 2009
Location: Dillsburg PA
Posts: 7
There's a bypass valve on the fuel rail.

I could be sticking, there is a procedure to check in the Hanes manual.
ytudrepus is offline   Reply With Quote
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