Inertia switches
 

Any of you guys that are running a fuel injected engine with electric fuel pumps using an inertia shut off switch? I'm not sure if I want to incorporate this into the build, from what I've been able to read about them a good sized pot hole could trigger it. I'm all about safety, but not at the expense of having to hassle with reseting the thing at every bad road we come across. Y'alls input as always is greatly appreciated. Thx.

You could go with the oil pressure switch set up but being injected it might run for awhile. None of the injected Fords I've driven have ever shut down on potholes or bumps. F350 dually was a rough riding truck too. Most of my trucks inertia switch in the right hand kick panel.

I still have mine intact, it has not given me any grief,never gone off and I've gone now some nasty bumpy roads.

OEM's have been using them for decades. I've never had an issue with any of my new cars with them. It's not something you hear about being troublesome in the news, and if cars were shutting down all the time from rough roads, you'd hear about it. I don't think you'll have any trouble with one, as long as the one you use isn't defective. I see no reason not to scrimp, here. If you were ever to be in a hard crash and the fuel didn't shut off, you could have a really big "hassle."

I appreciate all the input, do any of you have a part number for a switch thats tried and true? Thx.

Mines out of a 89 crown vic

The only issues I've heard about is when someone drives over a curb, etc. and slams the bottom of the vehicle against the pavement. Usually hard enough to jar your noodle. It's kind of a handy thing to have, not having the pump continuing to push fuel all over following an accident. Just place it somewhere not too difficult to reset and in the same orientation that it was in the donor vehicle (right side up, not sideways, etc.)

Yup mount it right side up Upside down or sideways may make it too sensitive. It has to be out of the weather or it will fail eventually. On the Panthers (Crown Vic, Grand Marquis , Lincoln Town Car) it is mounted on the passenger (right side) of the truck just behind (towards the back of the car) the deck lid hinge. Usually a quick slap on the quarter panel to that area is enough to trip it. Can be great fun to mess up your buds.

Below are a couple cut away's of the Ford inertia switch, they are the epitome of the "KISS" principle.


https://cimg8.ibsrv.net/gimg/www.for...7566d463bb.png
https://cimg0.ibsrv.net/gimg/www.for...c9cd263e15.jpg

Used mine as antitheft on the town car we used for trips. Stop at motel for night while unloading luggage I would tap the switch with tire iron. Load up next morning and push reset.

i've been kicking around the idea of using one on my truck, i just could never get see a straight answer on how to wire it. Through the ground wire to pump, through pump relay, through pump trigger wire coming from ford controls pack...
Let us know what you find out.

In trucks the inertia switch went between the fuel pump relay and the fuel pump cutting main power to it. The Interial switch should cut main power in the fuel pump circuit and not the control power to the fuel pump relay.

In my mind the less unnecessary stuff wired in the less chance of trouble . Why do you feel you need one ?

makes sense, I guess the only thing would be to make sure the switch that is purchased can carry the load of the fuel pump without any problems

Well besides being SOP for elec fuel pump installs, if you have an accident and rupture a fuel line the pump will just keep pumping fuel all over as long as the ignition is in on With EFI systems the volume of fuel it can move with no head pressure can be quite significant. It's a simple install that does not reduce reliability of the system it adds an accessible point for diagnostics, and really when was the last time heard of a Ford inertia switch failing ?