1999 v-10 Fuel Pressure checking procedure
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1999 v-10 Fuel Pressure checking procedure
How do I check the fuel pressure on a 1999 v-10? I have a Fuel injection gage but have read different threads on where and how to check pressure and test for 'bleed-down' of pressure and am a bit confused.
FTE Leadership Emeritus
Joined: Jul 2002
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From: Long Island USA
What would I do?
First, hook the gauge to the fuel rail.
At idle, with engine running, you should see 28-30PSI.
With engine off, key on, you should see about 38-40PSI.
With engine running, and vacuum disconnected from the fuel regulator (and plugged), you should see 38-40PSI.
Under load, foot to the floor, vacuum to fuel regulator connected, I'm not so sure, but it should be above 35.
Wait for others to comment, I might be crazy
First, hook the gauge to the fuel rail.
At idle, with engine running, you should see 28-30PSI.
With engine off, key on, you should see about 38-40PSI.
With engine running, and vacuum disconnected from the fuel regulator (and plugged), you should see 38-40PSI.
Under load, foot to the floor, vacuum to fuel regulator connected, I'm not so sure, but it should be above 35.
Wait for others to comment, I might be crazy
5th Wheeling
Joined: Oct 2016
Posts: 40
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Did you find a way to test the pump? My fuel pressure kit only has a 5/16 T fitting, so I can't test the pump pressure without the engine in line. The pressure regulator was replaced 4 years ago, and I am having a misfire code on bank 1. So, before I go down the road of replacing coils, I want to make sure the pump can deliver 45 psi.
Laughing Gas
Joined: Oct 2007
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The Schrader valve will be a fine place to check pump efficiency. With engine off ,key on the prime the rail , and gauge , cycle the key a few times looking for maximum preasure, then turn key off and watch to see how long it takes the pressure to bleed off .
5th Wheeling
Joined: Oct 2016
Posts: 40
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With the in-line gauge at the tank, the 3/8 line gets KoEo 32 psi, idle 34-36 & full throttle (parked) is 42 psi. 5/16 line is only 32psi.
In case anyone else is looking for the dead-end plugs - Dorman #800-330 & 800-337.
In case anyone else is looking for the dead-end plugs - Dorman #800-330 & 800-337.
Last edited by jziegler; May 19, 2026 at 06:19 AM.
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