Fuel Cut/Engine Shutoff Switch (Failed Attempt)

[millenniumtree]

'89 Civic 1.5L M/T

Well, today I failed to install a fuel cut/engine shutoff switch.
I bought a 25A switch for the dash and wired it up between the main relay and the injectors/fuel pump.

It cuts off the injectors and fuel pump just fine (I thoroughly checked/researched the Chilton manual to be sure of this). I thought that the worst it could do is throw an injector code on the ECU and then the injectors would re-activate when the switch was flipped back. WRONG.

Removing power from the injectors causes the ECU to flip out and not let the engine back on when I drop the clutch. (and it _does_ throw the injector code and activate the check engine light) So I basically still have to turn the ignition off and back on again, which defeats the whole purpose of the switch.

I've found a different place to wire the switch in, that should cut off more than JUST the injectors and fuel pump. It's the main 10A fuse that is only powered during RUN and START. (fuse 14 - for future reference)

I'll give 'er another go tomorrow. Hopefully with less mosquitos attacking me.

[bhazard]

Them skeeters get worse every year.

[cfg83]

millenniumtree -

You need yourself a handfull of these :

F & T Fur Harvester's Trading Post - Novelty Mosquito Trap


I have to do that mod also. I have heard that Saturn ECU/PCMs don't care if the fuel injectors cut out, but I have no personal experience that this is true.

CarloSW2

[Daox]

I'd recommend just cutting the injector signal, not the fuel pump. Fuel pressure should still remain during coasting, but I just don't see a reason to cut power to the pump.

[millenniumtree]

I think I'd get the same result if I just cut the injectors. Both injectors and pump are on a common wire, and I think the ECU would still freak out if I killed just the injectors.

I'm going to try today to tap into the fuse 14 output and I'll let you know how it goes.

[reformed]

Much better off cutting the spark instead of the gas IMO. The blue wire at the distributer, should do the trick on your car.

[millenniumtree]

Success Thread
Fuel Cut/Engine Shutoff Switch (Success!)