2003 5.4 EB Fuel Pump Relay

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Bedrck47

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Your welcome I wasn't trying to be a smart a$$ with the answer I understand you asking and making sure of the wire
 

Bedrck47

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See attached print
The connector with the dark green /yellow is C270K pin 3
The connector with the red wire is C270A pin 10

The jumper should only be used as a temporary means to bypass the contacts for the Fuel Pump Relay

F.P. Relay Jumper.jpg
 
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Bedrck47

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You may have to print the diagram in the previous post to get a better view
Have attached some better prints

On 24-03 look for C270a red wire
On 24-09 look for C270k dk gn/ye wire

Those are where the jumper gets installed
 

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CertusExpo

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So, after getting 100 miles to half a tank of gas, I realized the PCM is not just sending power to the relay but controlling the voltage therefore controlling the amount of fuel being supplied.

Now I'm wondering this. Could I just add a potentiometer like this one LINK to the circuit that would allow manual voltage control for low need scenarios such as surface street driving or stop and go traffic?
 

Bedrck47

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If you decide to replace the fuse box be careful Ford used two different fuse boxes in 2003 they are not interchangeable the replacement must have the same part number as the original

the complete part number is a combination of 12 numbers and letters

4 then 6 then 2 not just the 6 in the middle see the attached as an example

IMG_20140116_092601_505.jpg
 
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CertusExpo

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Thank you again because as a matter of fact, I'm getting ready to head out to Pick a Part.

By the way, what do you think of the potentiometer idea?
 
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CertusExpo

CertusExpo

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Have no idea if the PCM varies the voltage or not

I came across this thread LINK and please see the large paragraph under ***EXPLANATIONS***

"variable duty signal cycle to the fuel pump" which makes sense to me for fuel efficiency.

Edit: I'm also trying to avoid a situation like ExpyGirl03 had where she replaced the fuel pump relay only to have it burn up again by replacing it with an externally accessible and replaceable relay.
 
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