My Fuel Cut Switch write up with pictures!
 

Since I spent about a month finally getting around to doing this, I figured a little writeup with pictures will help others.
I have seen people asking how to wire this same switch (rat shack lighted 30amp 12v heavy duty switch).



Heres what I started with. 16 guage wire, switch, a 5 pack of male and female crimps- crimpers- cutters- tape- marker

http://www.iupload.net/082004/FCS101.JPG


Label your wires unless you want to track them when your done. If your like me, your girlfriend calls, and you get postponed for an hour or so......

http://www.iupload.net/082004/FCS102.JPG


This is the conenctor, it sits to the right of your steering colum. It has a yellow receptical, with a white plug, we are cutting the middle Black solid wire with the white stripe and brown marks, This varries per year and is being done on a 87 TII for reference. Connector is large circle, wire is smaller blue circle.

http://www.iupload.net/082004/FCS103.JPG

Cut the wire, and strip both the ends 3/8th's of an inch. Now I used a male connector on one side, and a female on the other. The reason behind this, if I ever want to undo or bypass a broken switch- I just unplug the switch wires and connect the two lines back together. Do tight crimps, we want this to last!

http://www.iupload.net/082004/FCS104.JPG

Now run the lines to where ever you want your switch- Mine is hidden in the ash tray, Be very carefully with where or whatever your drill into. For this switch- the wiring went as follows. Power, load, and ground. Run the ground to a close ground, then run the load to the plug side of the black/white/brown wire going into the white connector. Run the power line to the harness side of the black/white/brown wire.
Works like a charm and is lit when on :).

http://www.iupload.net/082004/FCS105.JPG

It works great so far. I realize I just told the largest rx7 community where my switch is, dont worrie, Ive moved it :). My bass knob goes there :).

Nice work. Im guessing this is for security, so no one jacks your ride? You can just turn off the fuel pump?

Seriously im not sure...

Im going to a college where 5+ cars are broken into a week.

I really dont want my car stolen :).

Yes I am doing this for security- people also do this to help with leaky injectors and hot start issues. By being able to turn off the fuel pump, you can de flood the car without having to pull fuses under the hood.

Very cool. I may do this!

yeah this saved me from having my vert stolen a few weeks ago. I used to have it setup this way but now I have the wiring straight to the injectors and it kills fuel instantly. And I use this to shut off the car everytime and when starting I crankit over twice then flip the switch and it starts everytime.

show me ow show me ow show me!!!

Thanks a lot for the write up!! My mom's Maxima just got stolen 3 days ago. YOu know I'll sure as hell be putting this in my car soon. Thanks Again.

sorry to ressurect... but

what would happen if you hit the switch while driving? would the car just die? would it be bad for the car at all?

The engine would just die of starvation, nothing really would harm the engine. But if you do make one for yourself, just put it in a place where it can't be accidently switched on/off.

ok cool.

I wonder if this will make my car start up faster at all? when its cold in the morning it takes like 3 seconds to start up. maybe its a little bit flooded or something? think this might help?

Yep, she'd just...die...

Hopefully you won't try this under boost, right?

n/a :)


what would happen if it was under boost?

If the switch was to the fuel pump your mixture would suddenly go super lean as the injectors continue to fire and drain gas from the system and your chances of predetonating would be most likely to expect to buy a new engine when you limp home. If the switch was to the injectors your engine would just die because the signal to the injectors would be cut off so they would just stay closed.

well thats worrying. does anyone know whether its to the fuel pump or to the injectors?

Just wire it up to the fuel pump and hide it so that you dont hit while driving.

anyone know before I go install the switch?

Just as an update, I went ahead and wired in the switch. works like a charm, operates as a kill switch and a theft deterant if left deactivated. 5 stars :)

I also have some red LEDs hooks up to the switch, so I know the pump is on when I see the soft red glow coming from around the moulding of the steering column.

this mods a go

Nice...

yo bukwild, how'd you wire it straight to the injectors? which wire?

I didnt do it to the injectors, it was to the fuel pump.

under the dash, right on the right side of the steering column, there is a connected plugged into a big yellow socket, you can miss it. you splice a switch into the black wire in the middle,a dn thats about it.

It was a DPDT switch so I also wired 4 leds to the other poles, connected my cigarette lighter 12V lines power into them and grounded em to the frame (I was too lazy to search for another 12V line)

The LEDs are barely noticible, so I plan to get some high brightness blue leds from radioshack so itll make a nice glow over the pedals.

but yeah, hit the switch, fuel pump and LEDs activate, toggle the other way when the engine is on and it dies within 3 seconds and wont start until it is reactivated. you can crank with it off and it wont start, but the second you turn it to 'on' while your cranking, BROOM

ill take some pics maybe once I get my other LEDs in there. if anyone has any Qs id be glad to take some pics of the wiring for you!

If you want to wire to your injectors here is the easy way. Locate the injector ground wire that goes from the firewall to the computer on the passenger side.(s4 NAs are a black wire with a yellow stripe) It is easieast to find this wire in the connector under the right hand passenger kick panel where it goes through a connector instead of at the computer because taking the kick panel off is easier(wiring diagram helps alot here). Do the same sort of cut and splice as shown at the beginning of the thread. Install switch where you please. This will make it so you can open and close the signal circuit between the computer and injectors and thus immediately shut off gas flow or disable your vehicle when you park and leave it.

I've got one of these, too. It's a covered toggle in the glove compartment. Kind of a bitch when you've got a girl in the car and have to reach over her, so put it somewhere more convenient. I like the sound of the ashtray, maybe I should relocate it.

just put this in today, works like a charm, this is definetly worth it and takes very little time and money

any idea if that wire is a different color on a n/a S5?

It's to the pump. Personally you worry tooooo much. The chances of hitting the switch if installed right, are close to nil. You'd have to work at it to turn it off while driving.