Kill switch how-to

[Impulse]

Originally Posted by bbjsw10

The way I have this drawn up on schematic it goes back to a normally closed position. I would not cut into wire by ignition switch shuts off more than you need to shut off. Like your ecm and odometer all in one shot, and the all important ABS system and airbags. This is why I would not cut ignition off at switch with relay. Plus need odometer to figure mileage. I have installed also since 1995 and was Install manager at local ABC warehouse for about a year.



FYI: the way you describe you have the relay connected on normal open contacts. 87a is normal closed.

Thank you for the correction

[Clev]

Can you guys suggest the proper way to do this for me? I have a '90 Accord (PGM-FI), and I coast and engine-brake down a 17.1 mile continuous decline in the morning. I tried leaving the car in 5th and turning off the key this morning. It worked great (kept me at about the right speed, the vacuum brakes still worked, etc.), but then I figured out that my speedo and odo were dead during the descent, so I can't compute mileage!

I'm thinking an actual switch to kill the injectors, but leave the ignition on. Any suggestions?


Thanks.

Tim

[bbjsw10]

Originally Posted by Clev

I have a '90 Accord (PGM-FI), and I coast and engine-brake down a 17.1 mile continuous decline in the morning

A engine-braking situation normally shuts off the injectors on its own, "Deceleration Fuel Cutoff" leaving key on and coasting down that hill in 5th or 4th would kill injectors. I could be wrong but I know most fuel injected cars do this. Mine does and it is a 91 Metro I am sure a Honda would be the same a little more advanced than my car is.

[Clev]

Originally Posted by bbjsw10

A engine-braking situation normally shuts off the injectors on its own, "Deceleration Fuel Cutoff" leaving key on and coasting down that hill in 5th or 4th would kill injectors. I could be wrong but I know most fuel injected cars do this. Mine does and it is a 91 Metro I am sure a Honda would be the same a little more advanced than my car is.

My only problem is that a) there are some times when I coast in neutral down this hill, and b) there are a few times where the car slows enough that I think the injectors are starting to kick in again, and c) the main relay is a weak point in this car, and I don't want to overstress it or my ECU by constantly turning the key on and off.

With the key off on today's experiment, I was able to go all the way down the 17.1 mile hill, shifting easily from neutral to 5th, and with instant smooth power delivery by turning the keyswitch back on for the 4 seconds I needed to accelerate over the one short uphill about halfway down. And of course, with the car in fifth, when I turned the key back on, it instantly came back to life without so much as a hiccup.

[KingsX]

Hi, I wonder if someone would be kind enough to clarify something for me. I'm no installer and I'm having trouble keeping this how-to clear enough to start the project. Even a napkin schematic would help. Anyway, the two major points I'm stumbling on is 1) What is meant by "jumper from 30"? If I'm already getting power from fuse block, it leaves no room for a jumper wire. And 2) Do I need a three pin switch or just two... and does it need to be rated at 30 amps or will a small one do since there's a relay? Thanks very much for the write up— I'm sure for the electrically inclined, it's all that's needed but for the "special" among us, a bit of clarification might help.

[bbjsw10]

Originally Posted by KingsX

What is meant by "jumper from 30"?


Do I need a three pin switch or just two... and does it need to be rated at 30 amps or will a small one do since there's a relay?

At 30 you can hook a small second wire in with the main wire from the fuse block, does not have to be a large wire at all. It is for the "control" side of relay very low amperage.

The switch can be a very tiny 2 post 1 side to ground and 1 to the relay.

Relays hardly draw anything amperage wise on the control side of it, that is the reason for relays. Large capacity with low current switches.

I can possibly get a close up picture for you of the relay how I did it, if this does not clear it up for you.

And Welcome to Ecomodders.

[KingsX]

Awesome! Seriously, now I'm at least headed in the right direction. I really appreciate you taking the time to even do the write up. I just have no practical experience with relays so I'd rather not render my Metro inop while I muddled through it. Thanks for the rapid reply and the warm welcome too.

btw- I lived in Findlay several years ago. I couldn't help but notice that detail under your avatar.

Cheers!

Patrick

[bbjsw10]

Originally Posted by KingsX

btw- I lived in Findlay several years ago. I couldn't help but notice that detail under your avatar.

You left in time to escape the flood then.

[KingsX]

Yeah, I moved long before the waters rose. Sounds like nothing was spared in the Midwest that year. I'm on higher ground now so I just have different things to be concerned with.

Thanks for the how-to. I finished it yesterday and it works like a charm. I now wished I'd either used a lighted switch or mounted it on the shift knob as you did. I assume you just took a drill press to the knob for routing the leads down and out through the boot.
That may be next weeks proj.

[bbjsw10]

Originally Posted by KingsX

mounted it on the shift knob as you did. I assume you just took a drill press to the knob for routing the leads down and out through the boot.

I actually drilled 2 holes one in top and another from low on front and made them intersect, that way avoiding threads of shifter.