Need to find fuel cutoff inertia switch in a 1996 ford ranger - will this cause fuel pum to not even hum? Can I hear fuel pump since it is inside gas tank? Can bad relay cause fuel pump to not work?

Fuel shut off switch may need to be reset. A friend of mine had it trip when he had a flat tire some years ago on ford car. The reset on his was behind the plastic piece to the right of where the video below. Video below shows fuel shut off/inertia switch on upper floorboard passenger side.
Inertia Switch Explained Removed and Replaced 98-12 Ford Ranger - YouTube
2002 Ford Ranger Fuel Cutoff Switch - YouTube
You can try swapping out your fuel pump relay to make sure the relay is not bad. Below link may help
1999 Ford Ranger Fuel Pump Relay, Fuel Pump Fuse & Starter Fuse Location - YouTube

Try crankshaft positioner. It needs to accurately report rpm to the ecm to kick up fuel pressure. Check Inertia switch for fuel cutoff and reset.

Only Ford products have inertia switches.
The fuel pump stops running after 10 min even with the relay jumpered ? ?

sounds like fuel pump in tank is not working. Can you hear it hum when you turn key to ON?

It should hum for 5 seconds and build up 40 psi of fuel pressure.

Can you hear the pump hum for 5 seconds when key is turned to ON?

Check & reset inertia switch (see onwer manual for location). Check Fuel pump relay after that.

PCM, computer turns on fuel pump relay when required.

Power relay turns on PCM when key is ON.

Hello tbrank56,

If you are looking for the inertia fuel shutoff switch it's located below the right hand side of the instrument below the glove box.

Regards,
netvan

Hello! Orange/Light Blue wire from Fuel Pump Relay to the Inertia Switch...Other side of Inertia Switch is Pink/Black wire that connects to the Pump...Other side of Pump is Black to chassis ground...

Guru..................saailer












I’m happy to help further over the phone at https://www.6ya.com/expert/david_6df67de3b14de867

Your vehicle has an inertia switch, which is located on the tow board to the right of the transmission pump. Usually the fuel pump does not shut off except in the case of an accident but you can check it anyway. Being fuel injected, your fuel pump is probably in the gas tank and if there is no power to the wires coming out of the tank, you probably have a bad fuel pump

Who cares if it is a safety system? my 05 won't even make it out of the driveway without the thing going off and killing my truck. All because I hit a pothole. If you know how, please tell us. I took it into the shop and the mechanic got 2 new switches from Ford and neither one fit. So either I am going to have spend another $1000 dollars because you have a moral stick up your you know what, or you could help us out.

I had this same issue. There is an inertia switch located below glove box. Mine went bad. Here is what I wrote to another person with the similar problem:

I have a 2005 Ranger Edge. I had the same problem. I did two things. First I replaced the fuel pump and it worked again for about 2 months. Then it stopped working again so I replaced the inertia switch with a new one from the Ford Dealership. It worked again for about a month. Than it stopped again, so I replaced the wiring that goes from the inertia switch to the main box on the bottom right passenger side. I also put the inertia switch inside the casing on the lower right so it couldn't be kicked. It has been working for 2 weeks now. I hope nothing else happens.

On another note, I had another electrical problem. My speedometer cluster stopped working and my mechanic found loose wires rubbing against metal on the inside. I think the electrical components on these Ford Rangers are just cheaply made. That is the only thing to check for you now. If it isn't the fuel pump or the inertia switch, just check all the wiring from fuel pump to inertia switch to make sure it is all done correctly. Also check all fuses for fuel pump/inertia switches.

Sometimes I say I and mean a mechanic, I am not a car expert, but would like to be.