Hot wiring fuel pump

[richtersand]

Hi all, I saw edwardb hot wired his fuel pump on his Coyote to get the pressure dialed in and the fuel primed in the system (thanks again Paul for the incredibly helpful documentation!). Did others do this? Is it necessary? Suggestions on the best way to do this? Thanks in advance!

[JohnK]

I did this after installing my rear harness and fuel system in order to pressure test the system and preliminarily set the pressure regulator. I used a Power Probe to apply voltage to the fuel pump wires at the forward end of the rear harness.

[Hoooper]

Fuel pressure normally should be set with the engine running, but if you want to do it pressure test your system it is a good idea

[edwardb]

Fuel pressure normally should be set with the engine running, but if you want to do it pressure test your system it is a good idea

Actually the Ford Performance instructions say to set with the pump running and the engine off. What the guys are describing here.

[Hoooper]

Weird. I never understood why it makes a difference if you arent vacuum referencing it anyway unless your pump is really borderline

[rich grsc]

The fuel demand of the engine varies by load, so the computer needs a set reference point. The computer will vary the pump run based on that.
This for a non-return fuel system

[Hoooper]

The coyote power pack includes a solid state relay for fuel pump PWM control?

[edwardb]

The coyote power pack includes a solid state relay for fuel pump PWM control?

Nope. Regular relay switching in the PDB. The crate motor setup runs the fuel pump at full +12V all the time in full return mode. The OE Mustang setup is a PWM controlled returnless setup. One of the big differences between the stock Mustang Coyote and the crate version with the Ford Performance controls pack.