# No prime?

**URL:** <https://community.cartalk.com/t/no-prime/44797>\
**Category:** Maintenance/Repairs\
**Tags:** wrangler, jeep\
**Created:** [February 20, 2010, 3:34pm UTC](https://community.cartalk.com/t/no-prime/44797 "2010-02-20T15:34:51Z")\
**Posts on this page:** 6\
**Page:** 1

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**Author:** ![pinhead102](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/pinhead102/32/1583_2.png) [@pinhead102](https://community.cartalk.com/u/pinhead102)\
**Post date:** [February 20, 2010, 3:34pm UTC](https://community.cartalk.com/t/no-prime/44797/1 "2010-02-20T15:34:51Z")

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it feels like I lose the prime to my fuel pump with the power offfor several hours. bad pump or fuel line fittings

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**Author:** ![mcparadise](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/mcparadise/32/32_2.png) [@mcparadise](https://community.cartalk.com/u/mcparadise)\
**Post date:** [February 20, 2010, 3:38pm UTC](https://community.cartalk.com/t/no-prime/44797/2 "2010-02-20T15:38:15Z")

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Check valve in fuel line.

Turn ignition to “ON,” wait 5 seconds for pump to prime system, then turn key to “START.”

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**Author:** ![Tester](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/tester/32/15976_2.png) [@Tester](https://community.cartalk.com/u/Tester)\
**Post date:** [February 20, 2010, 3:39pm UTC](https://community.cartalk.com/t/no-prime/44797/3 "2010-02-20T15:39:33Z")

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A bad anti-drain back valve on the fuel pump assembly will cause this problem. If you can get the engine to start by cycling ignition switch on/off several times before starting the engine it points to a problem with the anti-drain back valve. Unfortunately, it requires replacement of the fuel pump assembly to remedy the problem.

Tester

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**Author:** ![hellokit](https://avatars.discourse-cdn.com/v4/letter/h/6a8cbe/32.png) [@hellokit](https://community.cartalk.com/u/hellokit)\
**Post date:** [February 20, 2010, 4:00pm UTC](https://community.cartalk.com/t/no-prime/44797/4 "2010-02-20T16:00:12Z")

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How do you feel loss of fuel prime? What makes you think that? Is there a problem with starting?  
When the engine is turned off, the fuel pressure will stay up for several minuets—maybe a half hour.  
Normally, after you turn the ignition key to START, the fuel pump will run as long as the engine cranks; and, it will take 6 to 8 seconds to reach normal fuel pressure.  
If you want full fuel pressure first, turn the ignition ON for 4 seconds, OFF, ON for 4 seconds, OFF, ON for 4 seconds, and then crank the engine.  
The static fuel pressure can bleed off through the fuel pump, OR through the fuel pressure regulator, OR leaking fuel injectors, OR any other leak.

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**Author:** ![pinhead102](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/pinhead102/32/1583_2.png) [@pinhead102](https://community.cartalk.com/u/pinhead102)\
**Post date:** [February 20, 2010, 4:43pm UTC](https://community.cartalk.com/t/no-prime/44797/5 "2010-02-20T16:43:42Z")

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is the check valve at the pump or inline? in the past i didnt ave to wait the 5 seconds, i do that now cause it just cranks for 30 seconds before ignition

thanx

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**Author:** ![pinhead102](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/pinhead102/32/1583_2.png) [@pinhead102](https://community.cartalk.com/u/pinhead102)\
**Post date:** [February 20, 2010, 4:46pm UTC](https://community.cartalk.com/t/no-prime/44797/6 "2010-02-20T16:46:26Z")

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thanx!