The idea is to install a switch in the circuit to the fuel pump, hidden in a safe place. With the switch off and the fuel pump dead, the engine dies off quickly. The car will crank as usual, but won’t run for more than 5 seconds. The only way to steal your car now is to tow it or put it on a trailer.
You will need the following items for this mod:
- Wire cutter and stripper
- 10 feet of 12-gauge wire or one size smaller (length depends on where you want to put the switch)
- Exacto knife or razor blades
- Heat shrink tubing or electrical tape (heat shrink tubing is better – from Radio Shack)
- Soldering gun and solder
- A bunch of male/female connectors
- A switch (two pole). I got a rocker switch from Radio Shack that was rated for automotive use.
Now comes the creative part.
Find a place to hide the switch. I’d tell you where I put mine, but then I’d have to kill you. But here are some suggestions. Under the shift boot, you push through the boot cover to hit the switch. You may have to make a switch holder bracket; in the ashtray/cigarette lighter area; in the console compartment (too obvious); in the boot (painful to get to, but maximum concealment). Anywhere that’s a blind spot. I don’t recommend the glove compartment or under the dashboard. Too obvious. Remember, the carjacker has probably already disabled your alarm, ignition kill and starter kill systems. He’ll deduce that you have a poorly maintained car, or that you have another kill switch somewhere.
Remove any panels covering the fuel pump. You will find a round dohicky with a bunch of wires leading to it. Yes, dohicky is a technical term. Carefully open the cover of the bundle of wires leading to the top of the fuel pump. The bundle of wires splits at some point with 3 wires going to the fuel sending unit and low fuel connector and 2 wires going to the C566 connector and pump. Mine had electrical tape around it. Locate the yellow/green wire (the yellow wire with the green stripe). This is the power wire (from the ignition circuit) that powers the fuel pump. [If you are still confused about what is what, the wires to ignore are yellow/white, black/yellow, black/white & green/red. They are for the sending unit to the fuel gauge and low fuel light]. I used the yellow/green wire myself. Cut the wire. Strip off some of the insulation from both ends (just enough to connect with the male and female connectors). Find out where you want to install the switch. Figure out how you’re going to mount or attach the switch. If access to the wires is limited, wait until the last minute to glue, screw or bolt the switch in place. I super glued mine. Improvise.
Connect a new piece of wire to the wire coming out of the fuel pump. You have the option of hard wiring the circuit. However, I soldered a female connector to the wire coming out of the pump and a male connector to the new wire (more on this later). Use a hairdryer to shrink the insulation over the connection. You can also use electrical tape. Run this wire to your switch. Solder or use a female connector to attach it to one pole of the switch. Now take another piece of wire and connect it to the other pole of the switch (solder or socket connector). Run this wire back to the fuel pump area.
Connect the wire coming from the switch to the remaining or only loose end of the fuel pump wire (the one that goes to the circuit and finally to the power). Use a female connector on the wire from the switch and a male connector on the remaining wire. Insulate this with heat shrink tubing. The circuit is now complete. The reason I have a male connector on the wire coming from the power circuit and a female connector on the wire coming from the fuel pump is to have an emergency way of connecting the circuit if the switch fails. Just a failsafe backup. To keep all the wires from chafing or disconnecting, I used small cable ties to bundle the wires to other wires or points.
Test the switch. Start the car. If it starts, the switch is in the “on” position. Then turn the switch to the opposite position. The car should stop. Taaaadaaaa, the fuel pump is switched off. If the car doesn’t start in either position, you have a bad connection somewhere. Check the circuit again. You only have four places it could be messed up. The only other problem could be the cheap switch you bought from Target.
If it works, finish installing the switch. Hide it well. Reassemble all the panels. You’re in business. The only thing you need to be aware of is that you are going to forget about the switch. You’ll jump in the car, turn the key and it won’t start. Then you slap yourself on the back for forgetting (for the tenth time) that you didn’t turn on the fuel pump switch. Stupid, stupid, stupid. But that’s the idea. You want the thief to think that you’re a lousy car owner who doesn’t take good care of your car. Won’t start. A more experienced car thief will look for a mechanical fuel cut-off switch under the bonnet or some other device under the dashboard or glove box. If the switch is hidden and he doesn’t want to spend a lot of time looking, the thief will move on to an easier target.
This security modification is an inexpensive extra layer of protection. No guarantees.
