What is the function of the fuel pump shut off switch?

Okay, I know it’s to shut off the fuel pump, but when should it be used? I just rented a car from Hertz and they upgraded me to a Lincoln Town Car. Inside the trunk there was button to shut off the fuel pump. I tried to figure out the reason for it to be there.

First I figure it’s for a fire in the engine compartment. You’d want to turn the fuel pump off then for sure. The only trouble is, how do you get to it? If you turn off the ignition, the fuel pump stops by itself, and if you don’t turn off the ignition, the keys sit dangling from the steering column and you can’t get in the trunk.

I suppose if you were carjacked and stuffed in your own trunk you could shut down the engine, but once you’re in the trunk, you’re pretty much done for anyway, and it’s a little late for measures that will only piss off the carjacker.

It might be part of a security system. If you were to open the trunk and shut off the fuel pump a thief might not know how to get the fuel pump started again. Hell, I didn’t know either, the notice on the switch said to consult the owners manual for restarting instructions.

So, are these fuel pump shut off switches common? I’ve only seen two, both in the last two weeks, one in a Grand Marquis and one in the Town Car. Has anyone ever used one of these things and when?

AFAIK it’s for when you’re in an accident. Keeps your car from blowing up, as it automatically switches off the fuel pump. You are not supposed to use the switch to turn it OFF, but to turn it back ON.

When I was a kid my dad was driving me somewhere in the family Taurus when we were rear-ended during some heavy traffic. The bump wasn’t enough to hurt either of us but it was enough to shut off the fuel pump. He showed me how to go in the trunk and turn it back on so we could get ourselves out of traffic.

Huh!? I have never heard of such a thing. Seems like a reasonable invention, but I have to say I would be clueless if I drove a car with such a device. Does anyone have any idea how common they are? Is it limited to Fords?

Aha! That makes perfect sense. Thank you.

Do new cars even still have those. I remember in the early 90’s my parents cars all had them hidden in the trunk somewhere, but I haven’t seen them in years.

Minor nitpick: My brother had an engine fire in an MGB, and the fuel pump did not shut off, even after the ignition was off, even after the fuel line to the carbs was melted or burned off. Fuel was still being pumped onto the fire, until someone finally found some bolt cutters and cut the battery cables. It is possible, although it may only be possible in an MGB.

Ford is the only one of the big three to use them. Bear in mind that most vehicles now have the fuel pump located within the tank, such that the fuel lines forward to the engine are all under pressure and will spray fuel, if damaged. Personally, I wish it was a mandated safety feature.

My very first car, a Mercury Topaz, had that fun little button in the trunk.

I was tooling around a few days after I bought it when I took a shortcut through an industrial area and ran over some KILLER railroad tracks, which killed the car!

I was very upset. I walked to a payphone a mile away or so, and called my grandfather, who told me to call a tow truck.

Imagine my embarrassment when, after flipping out about how I was going to have to get a new timing belt or engine or something, the tow truck driver looked at the car, looked at me, and looked at the railroad tracks… and popped the trunk. He pressed that damned button and started the car right up. :eek: :eek:

I was so relieved that I gave the guy like a $40 tip.

I know my parent’s 98 Ford Windstar had one near the driver’s door pillar in the footwell.

Yes, my 2004 Escape has one. The switch to turn it back on is not in the rear, it’s next to the passenger-side door hinge.

I’ve only ever seen them on buses, I never realised a car had one.