Yup, thats the switch, if you pull the carpet away a bit you will see the connector and 2 wires on the bottom of it, with these if I need to check the switch for whatever reason, Ill just keep it simple, I will check the voltage level on the Dark Green wire first, then check for the same voltage level coming out on the Orange wire. Most of time you can do this without even having to unbolt the switch, although that will make it easier, but I would grab a cheap multimeter somewhere, (walmart, autozone etc). You just need to read DC voltage and resistance in some cases (Ohms). So you can get a cheap meter probably for $20 or so, and this is Harbor Freight's cheapest fuel pressure gauge that does come with the Ford adapter, its the most common adapter out there.
In this case, since we really dont know if that inertia switch is ok or not, you can do a couple things here, you can unplug the switch and jump the two wires together, just make sure youre using the same or higher gauge because the fuel pump pulls some amperage.
You can also do a voltage drop test across the two wires while its plugged in and the pump is running, you should read close to 0volts, meaning there is no voltage loss on the switch itself. This is very basic testing, so dont let the terminology get to ya.
I would do the testing first before jumping the switch out, unless youre comfortable doing that, it would eliminate the switch altogether for now. But seeing what the fuel pressure is doing is important, this might be something completely different than we think, so its very important we test so we dont change parts that dont need to be changed. That gets expensive.
HF has a meter for $5, cant beat that.
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Monday, August 25th, 2025 AT 10:23 AM