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Security mod: fuel cut off switch

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5.5K views 21 replies 15 participants last post by  dopeassjackson  
#1 ·
hey, apparently no one has posted this idea yet. My friend showed me a fuel cut off switch on his Civic hatch (B18'ed). When the switch is off, the car dosn't deliver fuel into the engine so it would just stall after starting it for 2 seconds to prevent theft. Basicly i think what it is, is a switch on the wire going to the fuel pump. Now, i've done some searching and apparently the black/purple wire. Can anyone confirm this? Also where does the wire run? It would be preferable if it were somewhere close to the drivers side. I would imagine if this works as planned, it would benafit most people on the forums, espeically the ones with a swapped engine or heavy modifications done to it.
 
#4 ·
correct me if im wrong, but is this not a "kill switch" ?

yes its a popular mod for the honda crowd... infact,. ive seen a car with even the ignition relocated and replaced with a starter button. which was very subtle in the way it was installed and looked perfect. the key hole , however, was not visible, so i dunno if he relocated it into the center console or what but it was nice.

but i would go for a kill switch. i think all u gotta do is tap into one of the ignition wires and reroute it to where the switch is, and when the switch is off, the wire is a broken connection. and vice versa.
 
#5 ·
just hook up a kill switch to the starter coil cause it wont start and it will make a starter noise cause the starter is not ingaging. when u go to start it up it makes a loud noise so if ur close by u will hear it. friend did it to his 280z but dont rememebr what he did lol I am sure u can just search for any kill switch or something like that. all u need is just wire and a switch maybe 20-25 amp
 
#8 ·
haha after fucking with my damn SR harness for weeks, I can tell you that a fuel kill switch is really easy to do. All you gotta do is locate the fuel pump relays (2 green boxes) and take a look at any of the wires going to them. There should be a fat power wire to each one, a fat black wire coming out of them to ground, and probably a thin green wire that goes to both. All you have to do is put a switch that interrupts the small green wire and now you have a fuel kill switch.

I plan on completely tearing out my key ignition and making a button push starter with an alarm system. I also plan on having several backup safety things, like the fuel kill switch, a battery interrupter, and a hidden ignition kill switch alongside the alarm. Each one of these things is a 5 dollar item and makes it just that much harder to steal the car.
 
#9 ·
Hm... lucky for me I only have to worry about the shit on the inside of my car being stolen b/c I live in lincoln NE. Cars being stolen around here aren't very common. So an alarm is good... worthless post... sorry
 
#10 ·
Shorty240 said:
Hm... lucky for me I only have to worry about the shit on the inside of my car being stolen b/c I live in lincoln NE. Cars being stolen around here aren't very common. So an alarm is good... worthless post... sorry

maybe to you its worthless, but to most of us, theft is a problem.

Dont crap on this thread, it has good info. Bug off.
 
#11 · (Edited)
sorry you must've understood me wrong. basically i was apologizing b/c my post was worthless. I really didn't have any info, or an opinion, but I like the idea of a switch that was described. Sorry for the confusion. Nice tail lights
 
#12 ·
I know what a kill switch is lol. but u can use it in many ways. Like u said for the gas pump, battery, starter coil, all good ways, I would do at least 2 of them. I need a Kill Switch for my lights!!!! anyone can help? I wan't a switch for my brake lights, tail, front, everything lol. My radio is hooked up 2 them so I can use my radio without a key. but my parkin lights come on, and I can't go to the drive in =( lol. oh well let me know if u know lol late
 
#14 ·
Silverbullet said:
dosn't the switch have to be the same current as the wire though? Does anyone know what current this is?

also does anyone know where the fuel pump wire runs?
The largest current drawn by any component is the starter motor, so a complete kill switch would have to handle the amperage of the starter, which i dont know off the top of my head.

The fuel pump power wire runs from the green fuel pump relays which are mounted just forward of the ECU.
 
#15 ·
rexbo said:
The largest current drawn by any component is the starter motor, so a complete kill switch would have to handle the amperage of the starter, which i dont know off the top of my head.

The fuel pump power wire runs from the green fuel pump relays which are mounted just forward of the ECU.
Not necessarily, you wire the kill switch to a relay which closes the circuit to the starter. That's how Nissan would do it :D

Seriously, that's how you keep large cuurent or large voltage sources away from human touch... relays!
 
#19 ·
ok I have heard that it was the black wire with pink strip on it... I tried that and nothing... I found circuit diagram and found that same wire but its for the fuel pump relay.. humm.. I also heard that its the black wire with purple strip on it, but just found on same diagram black wire with yellow commin from fuel pump... I am goign to look for the black and purple wire and let you kow if I found it. If anyone has any idea for a 89 240sx se let us know...
 
#20 ·
dunno if this helps, but for inconspicuousness this is what I did to my jeep:
Cigarette lighter is essentially a switch. Run your ignition relay wire (jeep ignition involves a relay, haven't messed with my 240's wiring harness yet so I dunno on this one) in one side of the cigarette lighter's two-wire harness, and the other side out to the ignition relay. Can't start the car without pushing in the cigarette lighter. It pops out on its own after a period of time so you don't have to worry about forgetting to flip it off or whatnot.

Just my 2c.

-cam
 
#21 ·
18 gage wire running from the pump around the back of the car and up past the driver on the left side. Clip it, hide switch whereever you want, and connect switch to clipped wire. WIRE is black/yellow stripe. I had this on my car before i rewired the chassis (fuel now runs with one relay and one switch). No need for an extra relay, or fancy switch. Simple, no fuel no start. Wire doesnt carry enough power/current to need a fancy switch. Pick up a switch (any kind) from Advanced, pepboys, parts america, etc. Goodluck and have fun, whole job should only take about 30min, most of that spent hiding the switch and finding the wire in teh bundle of 30wires next to the drivers seat.

BTW....WIRING DIAGRAMS THAT ARE FOUND ALL OVER THE NET IN FSM's (Factory Service Manuals) HAVE ALL THE IN INFORMATION TO PUT AN INTERRUPTER SWITCH IN ANY CIRCUIT TO DISABLE MUTIPLE OR SEPERATE SYSTEMS!!!!!!!! READ THE WIRING DIAGRAMS!!!!!