1997 - 2003 F-150

10 psi from shrader valve. 12 psi engine start.

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Old Nov 4, 2017 | 08:28 PM
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10 psi from shrader valve. 12 psi engine start.

So here's my next shin-dig.
F150 4.2 1999 215K MILES.

NEW FUEL FILTER.
New fuel relay
New fuel pressure regulator
10 psi key on 12 psi when it starts.

Fuel pump?
 
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Old Nov 4, 2017 | 09:01 PM
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You should be seeing closer to 30 psi.

Just to be sure, you are removing the schrader valve before checking the pressure right?
 
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Old Nov 4, 2017 | 09:05 PM
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Red face

Removing? What do you mean? I attached it to the valve and then turned the key. Explain the "removing" please.
 
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Old Nov 4, 2017 | 09:11 PM
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For the fuel pressure tester I own, the valve stem needs to be removed for an accurate reading.

I meant to say valve stem in my first reply instead of schrader valve, my bad.



 
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Old Nov 4, 2017 | 09:20 PM
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This is what mine looks like. It has a "Ford Adapter", then the Gage attaches to it.
 
Attached Thumbnails 10 psi from shrader valve. 12 psi engine start.-screenshot_20171104-211753.png  
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Old Nov 4, 2017 | 09:23 PM
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I have a similar tester made by Bosch.

You need to remove the valve stem from the schrader valve on the fuel rail before installing the Ford adapter.
 
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Old Nov 4, 2017 | 09:24 PM
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Ohh. I'm reading the instructions now. I just seen that. Do I use it the same way? Should their be a resting (keys on but engine off) psi?
 
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Old Nov 4, 2017 | 09:31 PM
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Yes you still use the tester the same way.

Place some paper towels under the fuel rail when removing the valve stem, some fuel will spill out.

I can't remember off the top of my head but you should be right around 30 psi with the engine off/ key on.
 
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Old Nov 4, 2017 | 09:34 PM
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With the engine on you should see 28-35 psi at idle.
 
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Old Nov 5, 2017 | 12:07 AM
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Specs are 28 to 40.
 
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Old Nov 5, 2017 | 12:39 AM
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^ thanks glc, I tried to reference one of your old post for the exact numbers but you have 35k lol.
 
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Old Nov 5, 2017 | 07:34 AM
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Some fuel pressure testers have an adapter that depresses the center pin of the Shrader valve when attached and do not require the core to be removed.

Check your specific test gear.

At key-on, you should have around 40 psi. When the engine starts and vacuum is applied to the regulator, you should see around 30 psi. This drop in pressure is expected and tells you that the regulator is working.
 

Last edited by projectSHO89; Nov 5, 2017 at 07:36 AM.
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Old Nov 5, 2017 | 07:58 AM
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Okay so yeah my adapter don't require my sv to be taken out. So I'm doing it right. Still have 10-12 psi at key on and during engine start. Also when it does start I have vacume at the regulator. So .... Where we at now? New fuel sending unit?
 
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Old Nov 5, 2017 | 09:45 AM
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fuel pump
 
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Old Nov 5, 2017 | 10:45 AM
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Ok fellas. I'm taking the bed off, I know the top bed bolts is a T50 but I have a spinner. Bottom passenger side is spinning. So what size is it?
 
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