An intersiting how-to article on fuel pump cutoff switch. Must read!!!

I found an interesting article reguarding a fuel pump cutoff switch. Its taken directlly from http://www.teamsolwa.com/ and the author Tom Whipple. I’ve just copied and pasted it here for everyone. All credit goes to Mr. Tom Whipple and the http://www.teamsolwa.com/ crew.

[I] Fuel Pump Cutoff Switch

DISCLAIMER : TeamSol of Washington or persons submitting the information here will not assume responsibility, nor be held liable for damage resulting from the use or misuse of any information contained on this page. In other words, any information you find here is used at your own risk.

FUEL PUMP CUTOFF SWITCH CHEAP SECURITY
For less than $10, you can make your Del Sol impossible to drive off by even the most determined car thief. The idea is to install a switch in the power circuit to the fuel pump. The switch is hidden in a really secret spot. With the switch off and fuel pump dead, the engine quickly dies. Car cranks like usual, but doesn’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 need the following stuff for the mod:

  1. Wire cutters and striper
  2. 10 ft. of 12 gauge wire or one size smaller(length depends on where you put the switch)
  3. Exacto knife or razor blade
  4. Shrink tube insulation or electricians tape (shrink wrap/tubes better - from Radio Shack)
  5. Soldering gun and solder
  6. A bunch of male/female connectors
  7. A switch (two pole). I got a rocker switch from Radio Shack that was rated for automotive use.

Step #1. Here’s the creative part. Find a location for hiding the switch. I’d tell you where I put mine, but then I’d have to kill ya. However, here are some suggestions:

· Under the shift boot. Invisible. You press through the boot cover to hit the switch. You might have to do some fabrication of a switch holder bracket.
· In the ashtray/cigarette lighter area (be sneaky)
· Inside the console compartment (too obvious)
· Inside one of the lockable storage bins (hmmmmm)
· Inside the trunk of the car (pain to get to, but max hidden)
· Any place that’s a blind spot. I don’t recommend the glove box or under the dash. Too obvious. Remember, the car jacker has probably already disabled your alarm, ignition kill, and starter kill system. He’ll deduce that you have a poorly maintained car, or you have another kill switch somewhere.

Step #2. Remove the back center panel (just pull off) and big storage bin piece (screws). You might need to undo the screws on the back of the center console (one screw in bottom of console cover area). Then locate the top of the fuel pump. It’s on the shelf where the storage bins rested, pretty close to the center. A round dohicky with a bundle of wires going to it.

Step #3. Carefully open up the cover of the wire bundle leading to the top of the fuel pump. The bundle of wires split at some point with 3 wires going to the fuel sending unit and low fuel connector, and two wires going to the C566 connector and pump. Mine had electricians tape around it. Locate the yellow/green wire (that’s yellow wire with green stripe). This is the power wire (from ignition circuit) that fires up the fuel pump. [If still confused on the what is what, wires to ignore are yellow/white, black/yellow, black/white, & green/red. They are for sending unit to fuel gauge and low fuel light.] I used the yellow/green wire myself. Cut the wire. Strip some of the insulation off of both ends (just enough to connect with male and female connectors).

Step #4. Locate where you want to install the switch. Figure out how you’re going to affix or attach the switch. If access to connecting the wires is limited, wait until the last minute to glue, screw, or bolt the switch down. I super glued mine. Improvise.

Step #5. Connect a new section of wire to the wire coming out of the fuel pump. You do have the option to hard wire the circuit . However, I soldered a female connector to the wire coming out of the pump and a male connector on the new wire (more about this later). Use a hair dryer to shrink insulation over the connection. Your option is to use electrician tape.

Step #6. Route that wire to your switch. Solder or use a female plug connector to attach to one pole of the switch.

Step #7. Now, take another piece of wire and connect to the other pole of the switch (female connector or solder). Route that wire back to the fuel pump area.

Step #8. Connect that wire coming from the switch to the remaining or only loose end 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. Shrink tube insulate that puppy. 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 from the fuel pump is to have an emergency way to hook up the circuit if the switch fails. Just a failsafe backup.

To keep all the wires from chafing or disconnecting, I used small zip ties to bundle the wires to other wires or spots. Use some duck tape and tape it down. Whatever.

Step #9. Test the switch. Start the car. If it starts, the switch is in the “on” position. Then, switch the switch to the opposite setting. The car should stall out. Taaaadaaaa, fuel pump is switched off. If the car doesn’t start in either setting, you have bad connection someplace. Recheck the circuit. You only have four places that it could be screwed up. The only other problem could be the cheap ass switch you bought at Target.

Step #10. If the switch works, finish the install of the switch. Hide it good. Reassemble all the panels. You’re in biddness.

The only thing you have to be aware of is that it is a given you will forget about the switch. You’ll jump in the car, turn the keys, and it won’t start. That’s when you slap yourself silly because you forgot (for the 10th time) that you didn’t turn on the fuel pump switch. DAMNIT!!! Stupid, stupid, stupid. However, that’s the idea. You want the car jacker to think that you’re a rotten car owner that poorly maintains his car. Won’t start. A more experienced car thief will look for a mechanical fuel cutoff switch under the hood or some other device under the dash or glove box. If the switch is hidden and he doesn’t want to spend a lot of time looking, the thief will split to find an easier target. This [I]security mod is a cheap, extra layer of protection. No guarantees.

Now, I could tell you how I’ve installed a second switch in that same circuit. The first switch is easy to find (car thief thinks “Ah HA!”), but I always leave that one in the ON position. The second switch is buried in the bowels of the car. That’s the real one. I’m not going to tell you where that one is located. MOOWHOOOWAAAHAAAHAAA!

Author Tom Whipple[/I]

This is a great idea and I just thought I’d share it with everyone who didn’t already know. I know its been touched on once or twice on here…but this goes into much greater detail.

This is specifiaclly for a delsol but can easilly be used for our cars. Correct me if I’m wrong…but I beleve the wire you would want to cut for our cars is yellow/black. Hope this helps some people out!!!

cool tip. so in our car is it the blk/yellow? I wanna be sure before i try this anyone know for sure?

Shouldnt matter what color the wire is, as long as ur pump isnt getting any power.

ok, so which wire would do that? sorry i dont know much about electronics and i dont want to cut a sensor wire.

Well, make sure ur looking at the pump, its right below the rear seat. There should be like 2 wires stick outta it (may be more, not too sure) and just cut it. I dont think theres any sensor wires down tehre, unless its the fuel sensor. But just make sure ur looking at the fuel pump.

nevermind i will attempt to find the wire myself, by the way there are 5 wires comming out of the fuel pump harness and im sure they arent all power and grounds. and im not gonna just cut anyone of um which is why i asked but thank you for trying to help.

hey sour_rain_808, did you ever find out which color is the power wire, i just took my seats off and im staring at the bundle of wires. dont know which one im supposed to cut. please let me know. thanx

EDIT: it seems to be the yellow/black one

Anyone find out if its the yellow/black wire to cut?

Just finished making my own fuel cutoff switch. Here’s a list of the items I bought to make this “kill switch.”

  1. 14 gauge wire
  2. 2 position toggle switch
  3. Shrink tube

Items which I also used to perform the installation:

  1. Soldering iron and solder (obviously)
  2. Wire cutters
  3. Splicer
  4. Electrical tape
  5. 10mm socket to take off the rear seat
  6. exacto knife

Remove the rear seat. There’s a 10mm bolt holding down the seat. Look in the middle of the rear seat crack. With the seat out, you will see a set of wires that go to the fuel pump. The set of wires is covered in a black plastic tube. Use an exacto knife to cut through the black tube. Be careful not to cut the other wires. Find the yellow/black wire, which should be one of the wires on the corner of the connector. Cut the yellow/black wire, connect and solder a wire to one of the ends (i even shrink-tubed the connection to make it look a lot cleaner), and with that end, connect it to one of prongs on the toggle switch. On the end of the other wire, connect and solder a piece of wire, and connect it to the other end of the toggle switch. This will complete the circuit. Make sure you leave enough wire length to where you want to put the switch. Very easy to do. Takes less than 10 minutes. Probably the only time consuming part is finding a place to put the kill switch. Test it out. If everything works properly, with the kill switch on the “on” position, the cars fuel should cut off, thereby turning off the engine. With the switch on the off position, car should start up perfectly. Total cost: Approx. $5.00 U.S

If you don’t have a soldering iron and solder available, you can just use electrical tape to connect the wires, but this should be just a temporary fix. Using solder will make the connections clean and permanent. There are many advantages using solder to connect the wires together as opposed to using just electrical tape. Take the time to do it right the first time and you won’t have to worry about it later. Hope this helps. Thanks to Leif and others who have posted about this “kill switch” tip. I can’t begin to tell you how much this integra forum has helped me and saved me TONS of money.

R,

Eric

Isn’t that the fuel gauge sending unit that we can see under the rear seat?

yes it is also the power line for the pump.

i put this in 5 months ago. my switch is inside the rear center ash tray. real easy to run the wires under the carpet for 8-12 inches.

i also used first a very small switch (non automotive) one day it died. licky i setup it up with two small plugs (fathers idea). the cheep one-time-use things and made them oposing directions so i was able to take the ashtray out, unplug the two wires, and plug them together. i was rolling in 2 minuets.

then i went to auto zone (not radio shack) and got an automotive switch.
mutch better now.

i do sugest making the switch bypassable (just in case) and using a good quality switch.

i just did it today. works very well. i got a switch and wire from Checker and soldered the wires on the switch, i drilled where i wanted the switch to be, fed the wires through the hole and to the pump. i cut the pump wire (yellow/black) and butt connected the wires from the pump to the switch. i saw the whole thing took about an hour and a half, but i ran into a few problems, well, i wouldnt call them problems, just hang ups. id say the hardest part about this install was either the soldering itself, or finding the 10mm ratchet to put the rear seat back on. i went looking for it everywhere to realise i left it on the hatch cover. the switch looks very clean and hidden. im proud :smiley:

just a hint.
you can also access this wire as its running along the door sill area (you can also trace it back to where ever it runs to).
just to the left of the driver seat, near the gas and trunk release, pull off the plastic holding down the carpet to the door sill.
have the car running while your cutting the wire and if it dies out soon after, then you hit the right one.

dont short out the wire to chassis ground!

isnt there a harness behind the dash also? the one behind that plastic peice on the drivers side where ur legs are, the one with the coin tray. cant you access the wire from there rather then the back seat?

what does that mean?

if you accidentally cut the wire to the chasis ground could you tape it back up or would it fuck something up really bad? :shrug: i dont know electronics

What he’s referring to is that if your car is on, and you short (connect) the 12V Yel/blk wire to the ground, you will blow the fuel pump fuse (i think it’s 15A)…causing the fuel pump to not work even when your switch is closed. Potentially leaving you stranded.

I wouldn’t fool with the wires when the car is on. According to the Helms guide, it’s the Yellow/Black wire which powers the pump.