I too am interested in doing the "injector kill switch". since my metro has only one injector it should be pretty simple. I'll try interuppting the circuit but if the engine computer starts throwing codes then a complete bypass circuit should work (like a heavy 2 ohm resistor or something).

If the injector switch makes the computer mad, a switch on the distributor coil pickup wire instead keeps it happy (provided you don't try to start the car with the switch "OFF").

I have a coil-pack ignition. I also had 3 wires. Unplug at coil. Take a test light, turn the ignition key on and the 1 hot wire is it. I found a nice switch at Advance Auto, about 5/8 inch round that depresses 1 side of the button and back. Also had a small led, good for dark nights. Splice the switch between the harness and coil, you're done. I first asked Metro about what he used way back before I was a member of GS.

Won't your ScanGauge stay alive if you key off then back on? You do have it set on hybrid, right? With the kill switch installed your ignition switch operates just as it did before. You just don't have to fiddle with it to kill the engine. The switch button just has to be on to run.

I did try wiring the switch between the engine fuse block lugs. It shut the engine off OK but also cut the power to SG at the same time. Maybe more.

With the hookup described above only the ignition is disabled by switch, everything ese that is on with ignition is still on.

Since then I have replaced the ignition kill with injector shutoff. I like this a lot better. The engine kills sooner and restarts cleaner. I actually used the same wire and switch I had used for the ignition kill.

since my car was stolen i redid a good chunk of wiring around my relays. so now i have a kill switch and i remove one of the relays.

i refuse to give specific online. i am sure most of you understand. anyway, i use it for security, not for engine off coasting.

Did you get your car back? Or get a different one?

Kill Switch usage?
 

Hello -

It sounds like some of you have a button that kills the injectors only as long as the button is depressed. Is this correct?

Question : For manual transmissions, do you press the button when the car is in Neutral or when the engine is engaged (i.e. the top gear, 5th gear in most current cars)? I ask because I think that if the transmission is in Neutral, the engine should turn off and require a bump-start. If the engine is in gear, I think it would just fire up as if nothing had happened.

Am I right? Which is it?

CarloSW2

cfg83, I replaced my ignition shutoff with injector shutoff. No need for both. Will kill engine in or out of gear. When I switch injectors off, engine dies immediately, quicker than it did with ignition kill and restarts cleaner. It does require a restart, either key or bump. You could rig a start button if you have an automatic that won't bump start.

CO ZX2 -

Thanks, I have a manual, so my life is easier for this stuff. I like the injector kill switch idea too. I know how to do the bump start from Neutral, so that is easy. I was hoping that when the car is in gear, taking my finger off the button of the kill-switch would restart fuel to the injectors, and would therefore restart the engine without having to bump start (less work for the driver). But it sounds like a bump-start is required for the Neutral or in-gear situation.

I was asking because from what I know about my car, it doesn't have an efficient "auto fuel shutoff" when my foot is on the brake. Hypothetically, when I am on the brake, in gear, and above idling RPM, the engine doesn't need much or any fuel to keep turning over. I have been told that this does happen for most fuel injected cars, but I can't gauge how my Saturn does this (at least not from the ScanGauge readings that I am seeing).

CarloSW2

cfg83: I was hoping that when the car is in gear, taking my finger off the button of the kill-switch would restart fuel to the injectors, and would therefore restart the engine without having to bump start (less work for the driver). But it sounds like a bump-start is required for the Neutral or in-gear situation.

If you are in gear engine will restart when switched on. Just the same as bump start. Why are people so paranoid about Engine Off Coasting, one of the most FE efficient things you can do??

CO ZX2 -

Great, that's what I wanted to hear. Please remember that I know *nothing* about cars. I was never a wrench monkey. When I had my CRX I opened the hood maybe 5 times in 5 years, and took pride in that (but am ashamed today). From what I can tell, at least 50% of the people on this forum have the car skills to swap a tranny if they want to. Everything I am learning right now is new for me (wide vs narrow band 02 sensors, what is that!?!?!?!).

Also, this is a forum that is *supportive* of this stuff. In the real world, I have to defend myself from very many detractors. My mechanic, who I have found to be very honest, didn't want to touch a fuel heater idea because of the fuel pressure/safety factors, and he has been working on cars since he was 12 years old.

If I kill this car, then it's off to the new car lot for me. I don't have the skills to fix it.

CarloSW2